An ancient anecdote, from the time of the Cold War, has it that a politician, physicist and astronomer were at a party, when the first two got into an argument about just how powerful the world's nuclear weapons were, and the right strategy for cutting stockpiles. They argued back and forth, and finally the physicist said, "Today's stockpiles are enough to destroy the world 30 times over". Before the politician could respond, the astronomer, feeling left out of the conversation, stepped in and said, "Ah, but even if that were to happen, it is not as if Earth is a major planet anyway."
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I have left the last of the four horsemen, and admittedly the one whose malcontent policies started it all, to the last. The United States may not realize this today, but the existence of the crescent mentioned above in essence destroys its claims to be the sole superpower. The US can no longer wage unilateral warfare against any country within the above-defined crescent, because the needs and reactions of natural allies need to be taken into count. Both Iran and North Korea are capable of gambling - and desperate enough to do so - that a first strike against the US will not lead to nuclear retribution as its neighborhood will be damaged as well. The US cannot risk nuclear fallout on Japan and South Korea, nor on Saudi Arabia and Israel.
A country that cannot stomach civilian losses and is limited from engaging in massive retribution will in essence have to rethink its strategic paradigm. In a matter of a few years, the US will go back to defending itself domestically from hostile forces, rather than projecting its power globally.
It is the end of the American century.
Asia Times