What happens inside the US is an internal US affair, and I refrain from commenting on that. I simply don't have the insight, and even if I did, I don't think I should tell you how to run your country. There will be some internal turbulence as government agencies and departments are being reduced/restructured, but in time you will find a new balance. It will pass.
But to abandon the world stage, which is the way the US now seems to be heading (particularly relating to Ukraine and Russia), is wrong on several levels.
It is morally upsetting to hear Trump and his officials blaming the victim of aggression, and at the same time sucking up to the mobster in the Kremlin. That is worse than the appeasement period leading up to WWII. There is a Right and a Wrong here, and Putin IS the bad guy. There can be no question about that - no gray area. For a long time, the US could be counted on to stand up for values of freedom and democracy, but it seems those days are over. By this I don't necessarily mean that the US should send troops and "fight other people's wars", but to at least isolate Russia economically via sanctions etc (as it has done up till now).
On a political level, alienating and upsetting long-term allies mainly in Europe, or neighbouring countries in NA, seems like Putin himself is actually pulling the strings. This includes threatening 'take over Greenland and Canada' and such stuff, as well as condoning the neo-fascist leaders/parties that unfortunately exist in some EU countries. This is a divide-and-conquer approach that should probably be directed towards opponents, rather than friends. But to his mind, we are perhaps no longer friends..
And from an economical point of view, starting a general trade/tariff war is utter stupidity. Nothing good will come of that. Unfortunately, the current US administration seems to be trying very hard to to create an image of itself as an unreliable and deceitful partner.
The only good that that could come out of this is that the EU gets some of it sh*t together, especially related to defence/military issues (we need to be able to defend ourselves, not relying on outside support). This has an economic angle to it as well. Many European countries have happily been buying a lot of US hardware in the past, but that may be subject to change. The know-how of how to build our own stuff is certainly there, it is just a question of political will to get organized.