I was recently read Diplomacy by Henry Kissinger. One of its arguments was that Germany, with a short history of being unified, did not have a grasp of how to reconcile its power with its newfound reach.
This got me thinking about the US. The US has been largely invulnerable for most of its history (with a brief exception in the War of 1812 and 9/11). Does American foreign policy suffer (like Germany) from lack of experience of having to deal with similarly sized great powers?
The United States wasn't invulnerable throughout history. You might be able to discount the attack on Pearl Harbor and the Second World War as examples of how America was not invulnerable to attacks from distant powers, as Americans had once believed. But after the Soviet Union developed both atomic weapons and the ability to deliver nuclear payloads to American targets, a sense of vulnerability became a cornerstone of the American approach to global politics. Indeed, Kissinger's own successes that he celebrates in Diplomacy were so important because they reduced the possibility of nuclear war between the Soviet Union and the United States.