After backing off the news for a few days and much thought, I feel that Trumps actions (not tweets or the wording he uses) regarding this Covid-19 pandemic has been pretty good. He has shown some interesting resilience and dare I say, a bit of benevolence. Actions do speak louder than words.
In regards the the question- Disunited States of America ?
I personally don't think the US is as divided as the media makes it out to be. I think before the age of instant communication, the people of the US have thought these things (political divided view points) and communicated them with their friends, family and peer group. To me it only seems "in your face" because its instant and much of the internet political, talk takes place anonymously.
Example - I remember when Bush Jr. was in office and I cant tell you how many people I knew threw or organized rallies in opposition to his policies. I even attended some, as some of those people were my close friends and I supported their right to express whatever they felt. They knew my stance on Bush Jr. , which was I liked him. They didn't seem to mind. So we were divided in politics but never as friends. Never before did I feel so close to people as I did then. To have differing views and still have each others back despite it.
I'm seeing that now. I have a friend, a couple of them in fact, that we just don't agree with the others stance at all. One I just hung out with yesterday and we briefly chatted about it and moved on with our day together (6ft apart). Another friend we have mutually decided that our friendship is much to precious to talk politics so we don't and low and behold we still love each other and check in to make sure the other is okay.
There are basic brass tack human emotions and needs that have nothing to do with politics. It is those places I see (choose to see) that I will continue to find common ground on a human level.
No big deal and this is not a humble brag at all but I've met Bush Jr. and Sr. on Bush Jr's ranch near Crawford, TX at a function. I can tell you that that dude works his butt off in the hot sun both on his ranch and serving the people (like a waiter) that were his guests. What you see on TV isn't always the best gauge of a person behavior or actions. Bush's private personality is really playful and funny.
Never met Trump but I can tell you that I have known some really spoiled rich trust fund babies that took their parents money and never hung out with them much less agree with/or align with them except for a handout of money. I do see Trump protecting his younger son from the media. I do see all of his adult kids in lock step with him. And he protects his wife from media onslaught. That speaks volumes, like it or not.
We are not as divided as the media makes it out to be.
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So can a US President unilaterally declare war? No. But do the same thing and call it a conflict or something and you are good to go.
There is much pressure behind a President to declare anything. It comes from many different angles. This seems to provide an accurate breakdown on war declarations in the USA.
https://en.wikipedia.org/wiki/Declaration_of_war_by_the_United_States