I'm sorry, but have you talked to any of these people?
The majority are angry AND crazy AND stupid.
Many of them believe that COVID does not exist, and almost all of them believe it's not a big deal.
Most of them believe that Obama is a Muslim from Kenya, and many of those believe his wife is transgender ("actually a man").
Nearly all of them believe that the whole climate emergency is a hoax.
More, they are uninterested in actually learning about the world. I still have some Trump-supporting friends on Facebook, nice people who haven't insult some mutual friend badly enough they had to be banned.
Even with something like climate change, where we have well over a century of science, and almost trivial physics you can demonstrate in your kitchen, and even with the greatest kindness, you can't reach them.
You explain how greenhouses work, and show them the numbers, and you get an answer like, "The Earth is so big that nothing humans do could ever change it." You point to all these "hundred year storms" and they say, "Newspapers will print any lie to sell papers." You point to articles by reputed scientists and they just shrug, "But you know it isn't true."
And every single election, they vote against their best interests. Against increases to the minimum wage, for endless warfare, against socialized medicine.
That said, I still agree with a big chunk of what you have written. The Democrats offer nothing except “Not the Republicans”. If they simply had regular people sit down and explain how socialized medicine works, people like me who spent years in the US and are now in Europe, it would be a hit — except they don’t want to offer socialized medicine. If they ran on a platform of cutting the pay of Congresspeople and Senators by a third, they’d be wildly popular, except they want the money. If they ran on an anti-war platform, where they pointed out that the US has spent $20 trillion dollars on warfare in the last two generations, that is almost a quarter MILLION dollars per family!, and that these wars failed to get anywhere, they’d be wildly popular, except they want the wars.
“Republican Lite” is not a winning brand. Unfortunately, with a two party system, this limp strategy works out for them. They win half the time, and then they become fabulously wealthy.
