The debris then quickly thins and cools asit expands , creating a supernova remnant .

然后，残骸迅速地变薄和冷却随着它的扩大，创造着一个超新星残骸。

That is certainly true of america today asit struggles to cope with economic stagnation , enervating foreign wars and waning self-confidence .

这正是当下美国的写照，美国竭尽全力应对经济停滞，无力应付外战及国家自信变弱等问题。