CNN  — 

Democratic presidential candidates have dragged their party to a defining ideological crossroads as they wrestle for a strategy to defeat Donald Trump.

At Tuesday night’s debate in Detroit hosted by CNN, east coast progressive icons Elizabeth Warren and Bernie Sanders warned against “spineless” moderation, selling “big ideas” of generational reform on health care, the economy and climate. Heartland moderates like Montana’s Steve Bullock and John Hickenlooper of Colorado hit out at “wish list” economics and liberal pipe dreams that would “FedEx the election” to the GOP.

At the end of the night, a key question lingered: Is most of America ready for the radical social and political change the most progressive Democrats are offering?

Warren offered the most compelling answer to that question.

“I get it – there is a lot at stake and people are scared,” she said. “But we can’t choose a candidate we don’t believe in just because we’re too scared to do anything else.”

The theme will be refreshed in Wednesday’s second debate when the most popular moderate – front-runner Joe Biden – will make a case that he is the most electable potential rival for Trump in a bid to bounce back from a shaky first debate in June.

The first of CNN’s two debates on successive nights in Detroit dramatically exemplified the crackling political energy inside the Democratic Party as the 2020 race hits a frenetic pace.

Instead of choreographed put downs and viral spats between rivals, the evening evolved into a passionate policy seminar on proposals and plans that if implemented could fundamentally realign life in America.

How the country – especially its crucial political middle interprets – Tuesday’s debate and the political combat to come, could end up deciding who lives in the White House after January 2021.

Before the next debates in September, the crowded field of 20 candidates could be halved by tightened polling and fundraising thresholds. But Tuesday’s debate showed this is an ideological struggle will endure all the way to the convention next year.

Fear of big ideas

Unapologetic progressives like Warren and Sanders sense that the audacious move right by the Trump presidency and the economic forces that birthed it offer an opening for a new liberal dawn.

“I don’t know why anyone goes to the trouble to run for president to talk about what we can’t do and what we won’t fight for,” Warren said.

Sanders, her biggest rival for the primary’s left lane who has long advocated a “revolution,” said, “I get a little bit tired of Democrats afraid of big ideas.”

But more pragmatic Democrats fear that radical ideas like single payer healthcare and a Green New Deal play into Trump’s warnings of socialism and would scare off moderate voters and replicate the most haunting Democratic defeats of the past.

“We can go down the road that Senator Sanders and Senator Warren want to take us, which is with bad policies like Medicare for All, free everything, and impossible promises,” said former Maryland Rep. John Delaney.

“That will turn off independent voters and get Trump reelected. That’s what happened with McGovern, that’s what happened with Mondale, that’s what happened with Dukakis.”

This is a debate that gets to the core of the modern Democratic Party itself. Should it hark back the New Deal and Great Society policy monuments of Franklin Roosevelt and Lyndon Johnson – who signed Medicare into law 54 years ago to the day Tuesday – or is the path back to power a recognition that in an age dominated by conservatives, the gentler more incremental and centrist progressivism of Bill Clinton and Barack Obama?

This is the fault line that exemplified by progressives who want to do away with private health insurance in a Medicare for All system and moderates who prefer a hybrid system akin to Obamacare.

A huge bet

History suggests that Democrats will take a huge bet if they chose the path of Warren and Sanders: No Democrat in recent memory has won the White House on such a radical platform.

As Minnesota Sen. Amy Klobuchar put it after stepping off stage: “I tried to make the case over and over tonight. … People are watching right now (and) they aren’t Democrat or independent.”

“They’re moderate Republicans and we need to win them to win the election,” Klobuchar told CNN’s Chris Cuomo.

Yet there was a reason why Warren and Sanders were in the center of the stage on Tuesday – they are the most popular of the 10 candidates in the first debate. They represent the powerful liberal forces that are taking the Democratic far to the left of where Obama left it.

The most fascinating question in the Democratic race is whether a liberal uprising that progressive candidates sense is in fact evolving in the country out of sight of the Beltway pundits.

After all, Washington is often the last to know about looming political revolutions – Trump’s 2016 victory is proof of that.

Trump has already seized on the ideological ferment in the Democratic primary, portraying the most progressive contenders as out of control radicals emblematic of a party that is charging fast to the left.

“Same radical Democrats. Same big government socialist message. Same winner of tonight’s debate: President Donald Trump,” said Kayleigh McEnany, national press secretary of the Trump campaign.

It is comments like that that have many pundits warning that only by sticking to the center can Democrats build the broad coalition needed to beat Trump. But Warren cautioned moderate opponents in the debate to avoid using “Republican talking points” to fault her policies on health care. And Sanders argued in a CNN interview that Democrats can only succeed by driving out a huge grassroots turnout that only ultra-progressive policies could stir.

By definition, Tuesday’s debate took placed in a controlled environment.

Many of the most progressive ideas advocated by Sanders and Warren – a state-run health care system – have no chance of being implemented unless Democrats rack up huge and unlikely majorities in Congress as well as wining the White House.

That’s an argument for a less ambitious approach that may not alienate centrist voters and give the GOP such fodder.

Another imponderable ahead of the election is whether voters will embrace a policy heavy candidacy or will respond to broad themes and atmospherics.

This was a point made by outsider candidate Marianne Williamson in the first Democratic debates last month, when she suggested Trump won in 2016 because of the clarity of his slogan “Make America Great Again.”

On Tuesday, the self-help guru argued that the Democratic policy pageant could leave the rest of the country cold.

“The entire conversation that we’re having here tonight, if you think any of this wonkiness is going to deal with this dark psychic force of the collectivized hatred that this President is bringing up in this country, then I’m afraid that the Democrats are going to see some very dark days,” she said.

One Democrat on stage on Tuesday, South Bend, Indiana, Mayor Pete Buttigieg, argued that clarity of leadership and conviction was just as important as the party’s ideological positioning.

“It is time to stop worrying about what the Republicans will say,” he said.

“It’s true that if we embrace a far left agenda, they are going to say we are a bunch of crazy socialists.”

“Let’s just stand up for the right policy and go out there and defend it.”