Sorry, but I have to say that the United States has never been a "peace loving" nation. I learned that in public school too, but a closer examination of history, especially the last decade, clearly lays that premise to rest. The U.S. was born in by way of war. The U.S. has never hesitated to use it's military for economic gain (Mexico, Central and South America from centuries past). I don't believe we had a valid reason for entering WWI. President Wilson had to so some fancy maneuvering to get the U.S. into it (General Smedley Butler can shed some light, circa 1930's). WWII was necessary, and Roosevelt saw the writing on the wall long before 1941. He had actually reinstated the draft, and, to the limits of his authority, began nudging industries toward fulfilling military needs. It's true that prior to December, 1941, Americans wanted no part in Europe's war (see WWI). Roosevelt had also been giving Britain military aid (Lend-Lease act).
After WWII, unlike after WWI, America didn't disarm. Not something a "peace loving" nation would decide to do. The "Cold War" with the Soviets was but a convenient excuse to continue to pour GDP into military might. The U.S. could have maintained military supremacy over the Soviets with a fraction of the amount of GDP actually spent.
The focus on the military industrial complex served, as an aside to this conversation, to allow other nations to take the lead in consumer electronics. By the end of the "Cold War", nary a TV, radio or any other commercial electronic device (save computers, but they went later) were designed or manufactured in the U.S. Ironically, the fact that military electronics are now essentially manufactured by a potential future foe (China) makes me feel even less safe than if China actually had a military strong enough to threaten the United States.