From the outside, looking in, I think you're wrong as I've said before (we're not having a fight here).
I think that having watched the correlation between our countries, it seems that messaging gets over BETTER in the US than the UK.
In the extremely short time that AOC has had a platform, she's turned politics on its head. It's interesting that Sanders has said almost as much before and rippled out waves, but AOC has turned out tidal waves. You have to ask WHY this has happened.
I think AOC's decision to knuckle up has paid huge dividends as the DEMs have been too nice before.
"You take the blue pill, the story ends. You wake up in your bed and believe whatever you want to believe. You take the red pill, you stay in wonderland, and I show you how deep the rabbit hole goes."
I think it's helped that Progressive voices have helped people take the political Red Pill when it comes to capitalism and how their hard work in making someone else's fortune barely pays their bills. That point is crucial and is a point that Kamala Harris championed in her town hall meeting. This is someone in the top echelon of the Dem party espousing such 'leftist' views.
Remember I said a while back centrists are stealing from Progressives as they have popular viewpoints. Of course medicare-for-all was virtually nonexistent outside of Sanders original championing! Now it's a staple diet for them.
The DEMs have actually realised how out of touch they are, hence the sudden amount of senators pledging a change of whom they represent.
They cannot serve two masters; the voters that vote them in to make a real difference to their lives or the Big Corp that pay them their fortunes.
Something I, too, have, mentioned before and it holds true, this brainwashing.
Having not lived in the States, you don't have full, personal context.
And there's an echo chamber going on here - if I'm not mistaken - viewpoints supporting your beliefs are given high credence - opposing viewpoints are devalued.
You need to separate what you would like to happen - from what will actually most likely happen. These things are absolutely not the same - and are likely diametrically opposite when you assess US politics.
This is my perspective - not as an outsider trying to grasp what's going on - but as a US Citizen who has a fairly good idea about what's actually transpiring.
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I'm 90% certain that a Socialist - running against Trump in 2020 would lose the election - probably by double digits.
Here's why:
1) Popular vote does not decide who wins presidential elections in the States, rather it's an electoral college system;
2) The electoral college - due to gerrymandering - favors conservative candidates - like Trump;
3) Older people vote much more frequently than younger people. Among older voters socialism is conflated with communism - many folks over 50 would never vote for a socialist regardless of their opinions about Trump - some subset of these putative anti-Trump voters will absolutely vote for Trump if the alternative is socialism;
4) America is very, very, very pro capitalism, at least among voters over the age of 40 (i.e., those most likely to vote) - the antithesis of which - is socialism;
5) The Democratic platform is pro-woman's rights - in favor of abortion except when past a certain stage of pregnancy where it seems that abortion is tantamount to killing a reasoning being (a highly-charged, controversial subject). But many US citizens are 100% opposed to abortion on any grounds whatsoever. A Democrat will never receive any vote from those with these beliefs - among which you can count devout Baptists, Evangelicals, Mormon's, Catholics, etc.
With due respect - there's virtually no chance that a socialist running against Trump in 2020 stands more than a snowball's chance in hell of becoming our next president. Unfortunately, a socialist stands a very good chance of becoming the Democratic nominee for our highest office.