I've never been an interventionist - in fact I think on this site we mostly agree that U.S. foreign policy has been an utter disaster since at least 2001. Thousands of American soldiers died in Iraq and Afghanistan, not to mention how we destabilized the Middle East. The destabilized Middle East left a power vacuum that ISIS was able to fill. Our foreign policy, in my view, has actually been counter-productive.
The United States spent trillions of dollars - enough to give everyone free college and healthcare during that time - on this war. Thousands of Americans died in the process. Hundreds of thousands of Middle Eastern people died.
Now, Trump has lowered us to a new level of incompetence by canceling the recent summit that was supposed to happen between the United States and North Korea. This comes after the U.S. backed out of the Paris Climate Accords - where we made a promise to the world to help reduce pollution - and after we broke the Iran deal - where we agreed with Iran that we and the U.N. could inspect their nuclear energy operations to make sure they were not making nukes.
No matter what you think of these deals, and I certainly don't love everything about them, backing out of these deals only serves to make the entire world not trust us. One of the few things you can do in foreign policy that will make everybody hate you is to back out of deals and show that nobody can count on you. After this, why would anybody ever make a deal or agreement with us again? We keep going back on our word.
If you personally knew somebody who was totally erratic, unpredictable, and went back on their word, would you want to make a deal with them or trust them? Of course not!
We could have potentially backed out of one of these deals or pushed for changes in several of them without doing too much damage to our reputation, but ripping them all up solved nothing and makes it clear to the world that making a deal with America is worthless. And that is a damn shame.
Now let's see how many more American lives and dollars are wasted over the next few years while we accomplish essentially nothing. It certainly looks like Trump doesn't actually have any specific plan to change anything.