Our Allies should rightly be concerned. The US has become more and more isolationist. The last major free trade treaty was under the TPP under Obama and both Hillary and Trump stated they would not support its passing.
The US is now energy independent and a net exporter. The US is also in the middle of the largest industrial build out in history which will bring much of our industrial plant back to North America.
In ten or fifteen years there will be no need for the US to get involved and keep sea lanes open like we are in the Red Sea. We can maintain a presence in the few areas that we deem critical.
My two sons will be of military age soon I would not support active involvement in any war that would risk their lives for Europe, Middle Eastern or other far flung countries when there is no real threat to mainland US. Supply military and financial aid, sure, but no boots on the ground. We don’t need to fight other peoples wars for them.
The problem is isolationism often leads to situations we can't ignore, as with the world wars. We were isolationists before then, and we benefited greatly from our international involvement ever since. We are the richest country in the history of the world largely thanks to our geography and international involvement. The dollar is the world's fiat currency. We prefer not to fight wars for other people, rather we usually just fund and arm groups that share our interests.
If we withdraw back into our shell, we lose the privileged place we have in the world.
I’d argue that the US greatly benefited from isolationism during the world wars, since all the main destruction happened in Europe/Asia.
This meant that after joining the war late and being in the winning side, they were perfectly poised to inject themselves as a global trade leader. Ironically isolationism brought about the globalist policy today.
