I don't know how you jumped to that conclusion. Opinions about Trump and opinions about the quality of the government are unrelated issues.
Because the primary focus is on Trump and not on the larger picture. Even here, as you say they're "unrelated issues," you're trying to bring the focus back on Trump and disregard everything else. They're most certainly
not "unrelated issues."
I've never heard anyone make that claim.
Really? You've never heard anyone ask "What would happen if you could go back in time and kill Hitler before he rose to power?" Such a question (and usually the answers) make the implied claim that history would have been different if such were to come to pass. Usually, it's implied within the general presentation of how events and individuals are often portrayed, particularly when it comes to pop culture history. (I'm not suggesting that actual historians make such claims, but the political perceptions of the masses don't generally come from historians anyway.)
In my opinion, Germany in 1933 presented a unique opportunity for a dictator to make a power grab that hopefully will never happen again in a nation capable of building a formidable army...
The German people were susceptible because they are human. They have their arrogant side like the rest of us. Hitler's appeal to their arrogant side that they belonged to a Master Race and were therefore entitled to dominate lesser races was eagerly accepted in that day and age. He used other appeals to arrogance as well:
Our nation is superior to theirs!
Our religion is superior to theirs!
Our race is superior to theirs!
Angela Merkel, the German chancellor, recently denounced nationalism as being morally wrong. She would have been shot for saying that in 1935.
Maybe, although there was nothing particularly new or unique about Hitler's message, as there have been nationalists in Germany for quite some time, even before Hitler was born. His ideas were already present in their political culture, so the idea of making it all about Hitler or the superficial trappings and symbolism of Nazism tends to miss the point entirely.
It's just part of a general trend in our culture which focuses on symptoms, symbols, and superficialities, while intentionally seeking to avoid the real problem.
Trump appeals to the arrogance in American citizens by saying that American interests should always be first; that America's problems are because of immigrants; that white supremacists are good people; and that the positions of Christian evangelicals should be politically supported.
We probably could have avoided that if Americans' principles had properly shifted towards a more anti-nationalist, anti-patriotic, anti-war, pro-civil rights stance that we briefly flirted with in the 1960s and 70s. Americans themselves chose to reject that, instead embracing a resurgence in patriotism and an even more intensive love of war and capitalism than this country had ever seen before. I would say that Reagan and his robotic followers (which included many Democrats) set us away from our previous ideals and put us on a path which has culminated with Trump. Even Clinton seemed to embrace that ideal.