In war, killing goes on until a victory is achieved.  For the United States the strategy of the Second World War came down to these two things: land bridges and ocean barriers. 

On the one hand, solid ground created “bridges.”  Where opponents were in direct contact, the fighting could never really stop.  Poland and Germany had been in contact in 1939; Britain, France, and Germany had been in contact in 1940; Russia and Germany were in direct contact from June 1941 onward.  In this kind of war, soldiers, small arms, artillery, fighter-bombers, and trucks were decisive. 

On the other hand, bodies of water, and especially oceans, created “barriers.”  The British staved off German victory with a ferocious defense of both the English Channel and the ocean shipping routes.  The Atlantic and Pacific oceans imposed huge obstacles to laying America’s military weight on the Germans and the Japanese.  Furthermore, most established sea-ports were in the hands of the Germans or the Japanese.  In the case of the Pacific Islands between Japan and America, they didn’t exist at all.  Invaders would have to go in over the beaches.  That meant landing craft.  Getting soldiers, weapons, supplies to a near-by launching point for the attacks meant a huge number of merchant ships.  Protecting those merchant ships required a great navy.  Anglo-American forces had to conquer water barriers to reach a land bridge. 

Until that could be achieved, the weight of the war fell on the Russians.  Countries have foreign policies for their own advantage, not for the advantage of other countries.  The Bolsheviks had made a separate peace with the Germans in 1918; Stalin had made a Non-Aggression Pact with the Germans in 1939.  If the Anglo-Americans appeared to be dragging their feet on getting into the war, then maybe he would strike another deal with Hitler.  Let the Anglo-Americans try to reconquer Western Europe in the face of the whole German Army instead of just ten percent of it.  So, the Anglo-Americans had to do what they could against Germany.  For a long time this meant the “strategic bombing” of German cities to reduce industrial production and perhaps to break the will of the German people. 

Warships, merchant ships, landing craft, heavy bombers, fighter planes, tanks, trucks, artillery, and small arms had two things in common.  They were made of steel and made in factories.  America had a lot of both, so it became the “Arsenal of Democracy.”  Two thirds of Allied military production—and half of the world’s total production–came from America. 

The United States mobilized almost 12 million men for the Army and another 4 million for other branches.  All these (mostly) men left the labor force while the demand for labor soared.  Women, Blacks, and Hispanics filled up the gap.  The US unemployment rate fell to 1.9 percent, finally ending the Depression.  High wages raised the standard of living. 

As soon as command of the seas permitted, the Anglo-Americans put their troops to use.  They invaded French North Africa (November 1942); Sicily (July 1943); Italy (September 1943); Normandy (June 1944); Southern France (August 1944); and Germany (Fall 1944). 

Meanwhile the Americans shoved back the Japanese.  Battling in jungles, on coral atolls, and on the high seas, the American advantage in industrial power and man power ground Japan into dust.  The war found its grim conclusion in fire raids and atom bombings. 

We had won.  What would we make of the peace, at home and abroad?