Not really morally or ethically acceptable to bomb the entire area. I agree with some things you say, but I think you take it a little too far on the other parts. The world does not only exist of Americans, nor does it only exist of Russians or any other ethnicity, race or culture. We are on this earth together and whether you like it or not, the actions of 1 man or country have consequences for other men or countries. I think Trump is right when he wants to put America first. He represents the people from the US so those should be his first priority. However, America first doesn't mean there's no second or third. It means there's still international relations. Things like chemical, nuclear or biological weapons are absolutely unacceptable and of course there should be a response to that. United States can't keep themselves away from that.
However, the response that they gave last night was a joke. Western countries are once again failing to show proof of who did it. Nope, instead there's a "high probability" that Syria did it. Where did I hear that before? Oh right, the Skripal case in the UK. There's a high probability that Russia did it. Russia meanwhile has been offering their help countless times to figure out what actually happened. UK meanwhile keeps slamming the door in their face again and again.
I think it was reckless and pointless to bomb. France, UK and US basically laid our lives in the hands of Russia, who said they'd attack the launching places of the missiles they fired on Syria. We all know what it means when a country attacks another country who is member of NATO.
I am not pro-russia nor pro-america. I just try to look at things from an objective point of view and lay down some theories (based on facts). Not saying this is my belief.