European social democrats glimpse hope in Bernie Sanders’ assertion at the Democratic National Convention on Monday that his progressive ideas are becoming mainstream, underlying the Joe Biden-Kamala Harris ticket.

Such a leftward turn would bring Biden closer to mainstream European ideas. But apprehension remains that the Convention’s big tent approach may unite some Democrats from the progressive left and center while failing to sufficiently reduce the divisions and hatred in the country to bring victory to Biden.

The unity being urged among Democrats could end in many Sanders’ progressives holding their noses to vote for Biden only to get rid of Donald Trump. Then the internecine squabbling could start again and stymie governance, especially if either of the two Houses is in Republican hands.

Whether there is a real rapprochement of views among Democrat factions should become clearer in coming days and weeks. Securing a Biden victory seems doubtful if the only real agreement is on the awfulness of Trump.

These are exciting times for American democracy because the stakes are so high. In effect, another four years of Donald Trump victory would put an end to progressive hopes.

They could also hurt Europe’s social democrats as voters may turn more willingly towards home-grown divisive leaders inspired by Trump. The Europeans will be relieved if Biden’s compromises with Sanders become a springboard for victory.

Covid-19 has created upheavals that have weakened Trump. But better numbers for both the coronavirus and the economy may give him the advantage in a photo finish.

Hilary Clinton won the popular vote but lost the presidency because she did not get enough votes in the right places for electoral college support. Biden could suffer a similar fate, especially if Trump also manages to bring troops back from Afghanistan and Iraq. He has already scored a small plus in the Middle East with the extraordinary deal between Israel and the United Arab Emirates.

The deep and extensive shocks of Covid-19 are convincing Americans of the need for changes and many see Biden as the better alternative to Trump. But the coronavirus has also lifted the veils on stubborn systemic issues, including deep rooted racial inequalities and economic unfairness.

These are early days, but Biden and Harris have an arduous struggle to win the trust of voters in their ability to deliver the profound and extensive changes needed as the US and the world emerge from Covid-19.

Sanders pointed out that “many of the ideas we fought for, that just a few years ago were considered “radical,” are now mainstream.” And remarkably, he vowed to work inside the big tent “with progressives, with moderates, and, yes, with conservatives to preserve this nation.” This might persuade his supporters to vote for Biden but that is not certain since moving towards the center is anathema to many.

Trump must be defeated because “the price of failure is just too great to imagine.” For Sanders, the future of democracy, the economy and the planet are at risk from the Trump administration’s authoritarianism.

The Convention’s star, Michelle Obama plainly warned, “If you think things cannot possibly get worse, trust me they can, and they will, if we don’t make a change in this election…we have got to vote for Joe Biden like our lives depend on it.”

Such words sound less like a willing unification of ideas and more like installing whatever temporary cooperation it takes to oust Trump. Still, European social democrats would be glad because they want to see the back of Trump. They are encouraged by Biden’s recent move leftwards to accommodate Sanders especially on climate change, the economy and health care.

But many Biden-Sanders proposals require implementation within five years and will cost trillions of dollars. That raises skepticism about Biden’s ability to remain true to the compromises he made with progressives. Instead, as President he might earn their wrath and become bogged down with splintered Democrats in a paralysis of governance.