Victor Davis Hanson

Japan and Germany, the world's third- and fourth-largest nations in terms of their gross domestic product, have never translated their formidable postwar economic strength into their past, prewar levels of military power. Yet both in theory could quickly do so -- and make nukes in the same way they make fine cars -- once they sense that there is no longer an unshakeable U.S. commitment and ability to shelter them from regional threats. In fact, an array of allies -- South Korea, Taiwan, the Philippines -- would all be frontline garrison states should the U.S. military vacate their bad neighborhoods.

The world is full of hot spots apart from the Israeli-Palestinian dispute. Shiite majorities in many of the Sunni-ruled and oil-rich Persian Gulf kingdoms believe that a terrorist-sponsoring Iran is more a liberator than rogue nation, and that Gulf oil has not been fully utilized as a strategic weapon.

The Aegean, Cyprus, the former Soviet Republics, the Falkland Islands, Central America and the Baltic are all deceptively quiet. Potentially aggressive actors in the region don't quite know how the U.S. military might react -- only that it easily could, and has in the past.

We lament the terrible American losses in blood and treasure in tribal Afghanistan and Iraq. But privately, radical Islamists acknowledge that the U.S. military killed thousands of jihadists in both countries -- and hope never to see U.S. troops on the battlefield again.

Of course, a country that can neither budget the necessary money nor maintain the will to oversee the international peace has no business continuing to try.

But in our relief from the vast costs and burdens of maintaining the postwar global order, we might at least acknowledge the truth, past and present: Just as the world was a far better place after 1945 because of an engaged United States, so it will probably become a much worse place due to an increasingly absent America.

Victor Davis Hanson

Victor Davis Hanson is a classicist and historian at the Hoover Institution, Stanford University, and a recipient of the 2007 National Humanities Medal.