The terrifying vulnerability of the U.S. military

Whenever a military crisis breaks out, American hawks talk about sending in the troops, and doves sputter about imperialism. But the key role of the U.S. military is usually far away from these hot spots, and instead in Eastern Europe, the Taiwan straits, the Korean peninsula, and the world's shipping lanes. Like it or not, in a world where the U.S. spends more on its military than every other country put together, and where the only plausible contenders with the U.S. for global predominance are...