sophie
Break My Heart
If you'll permit an outsider's perspective, the question is whether American society will accept and endorse something more than a moderate as far as the Left is concerned. That is, Bernie. Considering many Americans see anything remotely left-ish as the resurrection of the Soviet Union on US soil.
You may need to take it more gradually, and in that sense Warren seems more appropriate for this stage. It's unlikely someone will be able to just show up and "break down the system" right away without massive friction/stonewalling. Least of all in the extent of a single term (second would not be guaranteed).
Couple things.
1) Fiscally the US is much further left than traditional news media and conventional thinking give us credit for. Free College, Medicare For All, and the Green New Deal are all, broadly popular, even among Conservatives. The truth is that it's in the social stuff where the left generally loses the plot in building a coalition outside of the socially liberal urban populations in the US.
2) Donald Trump won in 2016. He did so, not by running to the center, but by embracing a combination of extreme far-right social positions (anti-gay/trans, anti-immigrant, anti-minority), and radical economic populism (not just the wall, but he was also running on universal healthcare, easing students' financial burdens, and bringing jobs back through state enforcement if necessary). The lesson to be learned from 2016 is that the center of this country isn't technocratic incremental change. That's the urban, elite left. The center is hurting, and has been hurting for a long time, and are drawn to populist leaders that speak to radical change that actually helps them, rather than incremental change which has long promised to help them but ends up actually doing very little.
3) Donald Trump also over the past 2 years has demonstrated that, while gridlock certainly does curtail a lot of a populist's agenda. The expansion of executive power over the last 50 years has given the President a lot of leeway to do as he pleases. And as long as the President has a vocal base and the will to use the bully pulpit to cow members of congress away from calling the President's bluff and triggering a constitutional crisis, the power of the much-touted "checks and balances" is actually quite illusory.
4) We've tried "incremental change". We've been trying it for 30 years. It took us 15 years to get Romneycare, which even in the mid-90s was a bone to be thrown to Right-leaning members of congress to build a bipartisan coalition. It didn't work. The fact of the matter is that "bipartisanship" is an illusion. It doesn't work and it's never worked. The great changes that have happened in this country - abolition, suffrage, workplace rights, the New Deal, and the Civil Rights Act - all came on the backs, not of amicable politicians bringing forth progress in the spirit of bipartisanship, but from large, organized masses from below threatening to burn those same politicians' houses down if they didn't accede to the peoples' demands. You can't legislate progress. Best case scenario you get something like Obamacare: a kneecapped version of an already extremely milquetoast piece of legislation set up to fail and be repealed ab initio. And even that a) wasn't even remotely bipartisan, and b) came on the back of a massive grassroots movement and a generationally-significant wave of Democratic victories.
So I say again: if you actually want genuine structural change, then you can't do what Warren's doing - promising to "have a plan for that," and asking everyone to place their trust in her to sort all of this out. Rather, you have to do what Bernie's doing: build up a large organized movement all shouting one message: give us these things or we'll burn your house down.

