(CNN) After three years of his chaotic presidency, President Donald Trump has made nostalgia a big, bold idea among Democrats. This is one of the secrets to former Vice President Joe Biden's ongoing success in the polls. The President, with the full support of his party in Congress, has pushed politics so far off-kilter that Americans are desperately yearning for normalcy in the Oval Office.

Julian Zelizer

On paper, Biden is not offering anything very dramatic. He himself embodies an older vision of the Democratic Party, in contrast to the slate of women, African Americans and Latinos who have made inroads in both the presidential race and in Congress. While his campaign has put forward a series of policy promises that aim to expand on President Barack Obama's domestic record, he often talks about a return to some kind of better past.

Biden has called for Democrats and Republicans to work together again. During the debate this week, he said that while he has "no love" for Republicans who attacked his family, "the fact is, we have to be able to get things done." Biden has frequently repeated a key tenet of his campaign: "We're in a battle for the soul of America." In doing so, he often talks about traditional American values that he respects and would champion as commander-in-chief. Even his "no malarkey" bus tour, which has been thoroughly mocked by younger generations, takes us back in time with the use of outdated slang.

Progressive critics point out that these promises evoke a past that no longer exists (and in many cases, never existed) and thus misleads voters into thinking that our country is in better shape than it is. His calls for bipartisanship, for instance, have rightly been met with deep skepticism given the radical outlook of a GOP that hasn't shown any interest in reaching across the aisle for several decades. Biden appeals to our better angels, but the Trump era has shown that those angels are too often absent from our polity.

But the criticism isn't undercutting Biden as much as it might in different times. And the reason is the President. Trump has blown up an already volatile political atmosphere with the way he governs. His vitriolic tweets, his aggressive use and abuse of presidential power, his punitive policies, his smashmouth attacks on opponents and his total disregard for the conventions and norms of Washington have created a toxic atmosphere where everything feels upended. To many Democrats, the nation is in a true state of crisis.

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