On the night of Tuesday, December 16, 1941, nine days after Japan’s attack on Pearl Harbor, six thousand students crowded into Hill Auditorium to sort out their options as the United States went to war.

For more than two years the campus had debated America’s role as war engulfed Europe and Asia. Now the debate was over, and students, especially male students, had their own decisions to make – whether to enlist immediately or to finish their education first.

Men on the faculty faced a similar decision – to volunteer and leave Ann Arbor or do their part at home.

President Alexander Grant Ruthven told the crowd at Hill: “You must determine what you can do best. If you honestly believe you will be of more value as a sailor or a soldier at the present time, you should offer your services at once.

“If, on the other hand, you believe education would increase your value in the struggle, then with no apologies to anyone, you should remain in school until you are called.”

Some enlisted right away. Many others took Ruthven’s advice to heart and stayed on for more schooling. Women, now in the majority at U-M for the first time since the start of co-education in the 1870s, weren’t welcome in the military except in small auxiliary corps. But they, too, were now expected to do their part for the war while still in school.

Those who stayed found themselves on a campus transformed.

In the jittery weeks after Pearl Harbor, some feared that America’s youth were too weak for war. In Ann Arbor, the loudest call for toughening up came from Col. William Addleman Ganoe, 60, who had just arrived on the campus as professor of military science direct from Army field maneuvers.

Early in 1942, in a blistering letter to administrators that was soon made public, Colonel Ganoe charged that Michigan’s male students, like U.S. collegians everywhere, included far too many “highbrow anemics.” These weaklings had grown up amid “various coquetting inventions and softening devices.” The result was “a hot-house, indoor, flabby manhood … the statistics of which are so discouraging that they are not published.”

“Something quick and drastic has to be done,” Ganoe urged, “if we are not going to be particeps criminis in the slaughter of our youth. … The fattest will fall and the fittest will fulfill.”

Every male student, he said, should get two hours of compulsory, strenuous exercise five days a week under the exacting eyes the Department of Physical Education and the Reserve Officer Training Corps, with weekly “lab” sessions in the Nichols Arboretum “under actual conditions of battle.” Not only leadership but “followship” should be taught.

Maybe Ganoe was the spur, maybe not. Certainly no one echoed his call for launching “a staunch reply to Hitler’s youth movement” at U-M, and one student critic remarked that Michigan men didn’t need a “demoniac propagandist” to prepare them for patriotic service. Still, by the summer of 1942, H.O. “Fritz” Crisler, director of athletics and coach of the varsity football team, had developed a compulsory fitness program.

In massed ranks on Ferry Field, men were put through basic calisthenics plus such drills as “The 440,” in which each participant sprinted in place for the equivalent of a quarter-mile. They ran obstacle courses with 7-foot walls and overhead ladders, taking two rungs at a time. There were competitions like “The Swat,” which started with six or eight men in a circle. One would be given a towel with a knot at the end. His challenge was to pursue the man to his right once around the circle, swatting his prey as many times as he could; meanwhile, his target tried to outrun him at top speed. Then the next two would go, and so on.

It wasn’t war, but it was a workout, and the program continued for the duration.

“When the time comes for you to answer the call,” wrote the sports editor of the Daily, Bud Hendel, “you won’t be soft and flabby with weak legs and short wind. You’ll be hard and you’ll be ready. You’ll be able to fight your own battle.”

But there was never any simulated warfare in the Arb.

At that mass meeting at Hill in December 1941, Alice Lloyd, the popular dean of women, had declared: “It is no longer true that though the men can rush out and enlist, the women have to take a passive part.”

Some women students, not many, departed for service in the women’s auxiliary corps — the WACs (Army), the WAVEs (Navy), the SPARs (Coast Guard), and the WASPS (Army Air Corps.)

Those who remained on campus came under pressure to do their own part for the war effort as volunteers.

Traditional extracurricular activities all but vanished. Sophomore women dropped the Sophomore Cabaret to become hospital volunteers. In place of the Junior Girls Play, junior girls sold War Bonds and War Stamps. Senior women prepared medical dressings for the Red Cross.

New classes sprang up to prepare women for war work, though none for course credits.

There were classes in first aid and home nursing to help the wounded. There were classes to prepare women to help fill the critical shortage of typists and stenographers in war production factories. Classes in motor mechanics covered repairs, maintenance and truck driving. Classes trained women in nutrition to staff the new national nutrition programs. There were classes in child care to support mothers employed on war production lines.

Calls for women to do their part came with strong doses of shaming. Students on the Women’s War Council urged their sisters: “You are the women privileged with the best in education, in training. You must make yourselves worthy of this privilege. … There must not be one among you who is shirking.

“Women of Michigan, it is time to awaken. It is time to put away your ‘coke’ sipping and bridge games and all-night bull sessions. It is time to rip days off the calendar without a sense of wasted hours. It is time to read the morning headlines without a guilty conscience.”

Whether they pitched in or not, women found themselves on new ground.

Month by month, as more and more men departed for military service, women took key roles in student organizations long dominated by men.

In the sciences and engineering, women suddenly found new opportunities in classrooms where they had been regarded as oddities. Students even launched a Society of Women Engineers.

Student publications, heretofore bastions of male influence, fell to the invader quickly. Women were named editors-in-chief of the Michiganensian and the Gargoyle. In the newsroom of the Daily – though its editors-in-chief were male throughout the war – women predominated.

“In another year,” a yearbook editor remarked, “even a 4F [a man disqualified from war service by a physical limitation] will be a phenomenon on a Daily staff of dictatorial women.”

In the early months of the war, certain alarmists in the vein of Colonel Ganoe urged President Ruthven simply to turn over the campus to the military as a place to house and train thousands of soldiers and sailors.

Ruthven wouldn’t have it. The war would end eventually, he reasoned, presumably in victory, and the state would once again need its university. In the meantime, he believed, the institution still had its basic job to do – preparing students for whatever work they were about to take on, whether in war or peace. So classes would go on.

At the same time, Ruthven and his advisors decided to make the University wide open for cooperative ventures with the War Department. What a university was good at, U-M would do: education.

Thus began an invasion by servicemen in and out of uniform.

* * *

The first to arrive were trainees for the Army’s Judge Advocate General Corps (JAG), the Army’s lawyers. They filled the Lawyers Club of the Law School in September 1942, and normal enrollment dropped by 90 percent. The Law School would train nearly 2,500 JAG lawyers by the end of the war. (For a time they were served their meals by Italian prisoners of war, who played soccer in the courtyard on breaks.)

On the other side of the world, as the Army and Navy fought their way back across the Pacific by a series of stepping-stone islands, intelligence planners realized that men were needed to act as Japanese-English translators. They reached out to educators, and U-M said it could help.

To run the program, the Army tapped Joseph Yamagiwa, a native of Seattle who had come to Ann Arbor in the 1930s to join the staff of the Early Modern English Dictionary. He completed his Ph.D. shortly after the U.S. entered the war, in time to place his training in languages at the service of the Army.

Yamagiwa found many recruits among the Japanese-Americans whose families had just been interned by the U.S. government in the wake of the Pearl Harbor attack. Others had no Japanese ancestry.

Early in 1943, East Quad was emptied of regular students and the students of Japanese moved in. All were put through an intensive 12-month training regimen, then sent to the Pacific. The program continued through December 1945.

* * *

West Quad, too, was emptied out. In came the Navy, and the dorm was soon being called “The Ship.”

Some 1,300 apprentice seamen came to U-M for accelerated college degrees. Most studied engineering. Some took courses in medicine and dentistry. Students in the expanded Navy ROTC program joined them.

Unlike their counterparts from the Army, the Navy men were allowed to take part in intercollegiate athletics, and they filled out the rosters of varsity teams in the war years.

* * *

U-M faculty trained Army Air Corps men in meteorology. The Army sent contingents to study the history, geography, government and culture of European countries as well as Japan – they were being prepared to oversee postwar governments in the defeated Axis nations. The Navy sent men to Michigan’s vaunted Department of Naval Architecture to learn how to design ships.

In all, U-M trained 4,000 men for the Navy and Marine Corps; 9,500 men for the Army (including 1,500 Japanese speakers); and some 12,000 civilian contractors.

More than 220 faculty members, a substantial fraction of the total, left Ann Arbor to take positions in the government and the military services.

Meanwhile, as young soon-to-be soldiers jumped and jogged on Ferry Field, many Michigan scientists dove into war work in quiet laboratories with double-locks on the doors.

The Allies knew that victory or defeat might hang on the outcome of what Winston Churchill called “the wizard war” – the competition between Allied and Axis scientists to develop weaponry powered by sophisticated new technologies.

Of course the best known such effort in the U.S. was the Manhattan Project, which developed the atomic bomb. But many others had their impact in the theaters of war.

One of the most important had begun in Ann Arbor amid headlines of the distant London Blitz of 1940-41, when German bombers discarded their attacks on military targets and began an assault on the civilian neighborhoods of the British capital.

British fighter planes could knock down only so many of the invading planes, and it was even harder for anti-aircraft gunners to hit the planes from the ground. To destroy a German bomber with “ack-ack” fire, British gunners had to fire their shells like a quarterback aiming for a receiver by a mile or more – though in this case, the target could twist and weave to avoid the rising missiles. There were timers in the shells that could be set to detonate the explosive after so many seconds in the air. But that, too, required exquisite timing and an enemy target that didn’t duck.

Then Allied scientists had an idea. What if a shell high in the air could beam an electromagnetic signal at a German bomber? The radio signal might bounce back to the shell and detonate the explosive. It would be a fuse that worked like the new technology of RADAR. Within a hundred feet or so of its target, an exploding shell could destroy the plane without actually hitting it.

But was it feasible? The best experts in radio wave technology were asked to find out. Two of them were Michigan’s David Dennison and H. Richard Crane, professors of physics. (U-M’s Physics and Astronomy Building would later be named for Dennison.)

“This was at a time when physicists were by far the best radio people,” Dennison told an interviewer many years later. “Any innovation at that time would have been done mainly by physics people.”

Under the hush-hush aegis of the National Defense Research Council, and in coordination with British scientists and other American specialists, Dennison and Crane began their work.

There were vexing problems. Radio equipment composed of glass tubes and flimsy circuits were delicate. Yet these tubes and circuits would have to survive an explosive launch from a cannon. The parts had to be very small, too, to fit in a five-inch artillery shell. And there still had to be a reliable timer, to make sure the radio wave wouldn’t set off the explosive early and kill the artillery crew.

In a secret outdoor setting near the campus, Crane supervised two dozen scientists in making some 50,000 tests on copper model planes that raced overhead on pulleys. By peacetime standards, the experiments proceeded as swiftly as the experimenters could manage. The results didn’t come quickly enough to halt the Blitz. But by mid-1942, with the U.S. now in the war, the “Variable Time Proximity Fuse” was ready for testing in battle conditions.

After the disaster at Pearl Harbor and a close-call victory in the Battle of Midway, the U.S. Navy, in particular, was desperate to see the new fuses work. A high-ranking officer on the project said every month of delay equaled the loss of one battle cruiser.

The test came on August 13, 1942. In Chesapeake Bay, three unmanned drone planes were sent high over the U.S.S. Cleveland. Controlled by radio transmitters, the drones zigged and zagged like barn swallows. But the gunners of the Cleveland brought them down with only four shells.

With that, the fuses were rushed into production. U-M’s Professor Dennison supervised a team that analyzed their performance in battle and designed improvements. The fuses spread to the Army, which used them to great effect in the climactic Battle of the Bulge in Europe, and to the British, who slowed the onslaught of German “buzz bombs” with proximity-fuse shells.

* * *

The work of Dennison and Crane on the proximity fuse was only one of some 200 secret research projects undertaken by Michigan scientists during the war.

Other researchers figured out how to accelerate the production of a key explosive used against Axis submarines. U-M contributed to radar technology and the Manhattan Project. Four mathematicians developed a theory that was critical to the development of bomb sights used by the Army Air Corps. Floyd Bartell, a chemistry professor, invented a synthetic fabric called Aerobond for uniforms that kept wearers warm and dry; it was tested in a U-M swimming pool.

Ten days after Japanese leaders formally signed surrender papers in September 1945, U-M President Alexander Ruthven received a letter of thanks from Brehon B. Somervell, commanding general of the Army Service Forces.

“Your institution has played a very important part in producing the material which has been such a decisive factor in winning the war,” Somervell wrote. “You and your associates must have a deep sense of satisfaction as you look back upon your accomplishments for your country.”

On May 8, 1945, most of Ann Arbor’s stores closed in observance of V-E Day — “victory in Europe.”

That night, store owners turned on their lights for the first time in years.

“It seems kinda funny to see the lights on,” an Ann Arbor policeman remarked to a Daily reporter. “But we’ll get used to it in time.”

* * *

Three months later, just after 7 p.m. on August 14, a roar went up in West Quad – the radio had just confirmed news of an end to the war in the Pacific.

Students ran into the streets. Honking cars flooded State and Main, where the crowds soon stretched from one side to the other for blocks.

Police, to their surprise, were delighted by the students’ self-control. “They seem to be exercising exceptionally good judgment,” one said.

* * *

On June 21, 1946, representatives of all the military branches stood at attention on Washington Street facing the Rackham Building.

Inside, a memorial was held for the 474 U-M men and women who had died in the nation’s service during the war.

Principal sources included “Michigan on the March: The University of Michigan in World War II” by Brian Williams; “A University at War: Michigan’s Record in Review”; Women at Michigan: The ‘Dangerous Experiment,’ 1890s to the Present, by Ruth Bordin, et al; “Interview with Professor David Dennison” in Histories of the Michigan Physics Department; The Michigan Daily; and the Michigan Alumnus.