Yeah, what you are doing here is making way too many assumption. Firstly, just because someone is anti-Trump, doesn't mean they want the country to fail. I've seen way to much of this nonsense on Fox pundits. They are anti-Trump because they think Trump is failing the country.The exceptionally vile thing going on are the people who would rather see the country fail than Trump succeed.
Secondly, just because you disagree with policies doesn't mean you are trying to destroy America
Third, just because Trump is the leader, doesn't make his failure lead to the countries failure. In fact, there have been quite a few instances of presidental failure leading to the betterment of America. Obama is case in point
Fourth, do you have any proof about people wanting to destroy their own country? Because here's what I hear: Trump did ______ to Americans and that's destroying America. I DO hear a lot of conservatives say, 'if you don't follow tradition, you'll ruin America.' It's basically Fox and Friends tag line
Fifth, exceptionally vile? Has any of these people's decision lead to someone's deaths? Because Trump's decisions have. Has any of their decisions lined their pockets or those of their buddies? Because Trump's decisions have. Has these comments lead to trade wars that negatively effect the economy? Because Trump's decisions have. Has these exceptionally vile thoughts lead to firings based upon them not agreeing with the president? Because Trump's decisions have. But sure, mean internet guy is way more vile. None of these 'exceptionally vile' people have done as much damage to America as Trump (or any president) has.
Lastly, at best, what you could say is that these people want to see TRUMP's version of America fail. His version isn't the ONLY version. There are plenty out there.
Edit: You dont think Reagan and Bush 1&2 were demgogues?