Once the Democrats solve their existential crisis it will be back to the trenches with the Senate as their weapon

For the time being the party will shift to the liberal, more confrontational wing of the party – led by Bernie Sanders, 74 years old but who in the primaries struck a populist chord Clinton never could

California’s attorney general Kamala Harris is tipped to be the next leader of the Democratic Party (AP)

The driving rationale behind Donald Trump’s astounding victory – more powerful even than his supporters’ loathing of Hillary Clinton, or their pain at lost jobs and dwindling economic opportunities – was disgust with Washington and the political status quo, and the utter failure of both parties to address their plight.

The talk, as always at such moments, is of unity and a new beginning. Alas, even the biggest upset in American political history is unlikely to bring the “forgotten America” much comfort, beyond the satisfaction of revenge.

You can paint a cheery scenario that the sheer shock of what happened on Tuesday, November 8, will bang sense into heads on all sides. But in Washington, only a void beckons on the day after.

The reckoning has been a long time coming. However, if an old order has been upturned, no-one knows what will replace it. Trump is untested. He has never been elected to any office. He promises to use his business skills to fix America. But beyond sweeping generalisations, what he will do, whom he will choose for his cabinet, whether he will even partly make good on the blood-curdling promises of the campaign, remains mysteries.

Adding to the confusion is the extraordinary role reversal of the last 24 hours. The election was supposed to end with a resounding Trump defeat and Republican civil war. And the party is indeed split. But to its own amazement, it has emerged with total control of Washington. There is no more effective healer than victory, especially since Trump’s coat-tails proved strong enough to preserve the Republican majority in the Senate. Whatever else he lacks, he has a mandate.

Instead it’s the Democrats who are in existential turmoil. Clinton’s defeat has ended an era, sweeping away the party’s dominant political machine, leaving a cupboard that is disturbingly bare. Most of its Congressional leaders are old. Republicans constitute an overwhelming majority of governors, a traditional presidential talent pool. A measure of the vacuum is that many Democrats see their best hope as the new senator Kamala Harris, California’s attorney general but a virtual unknown on the national stage.

For the time being the initiative will surely shift to the liberal, more confrontational wing of the party – led by Bernie Sanders, 74 years old but who in the primaries struck a populist chord Clinton never could, and Elizabeth Warren, the anti-Wall Street crusader who also thrilled crowds on the campaign trail.

A familiar post-election ritual is unfolding. Trump in his victory speech early Wednesday set the pattern, urging a divided country to come together, and pledging to be the president of all Americans. In her formal concession speech, Clinton was expected to be equally gracious. There will be a truce, born in part out of sheer exhaustion after a brutal campaign. But after that?

Bitterness runs deep. Throughout the eight years of the Obama presidency, Republicans have sought to thwart him at every turn, refusing every compromise. Democrats would not be human if they did not seek to respond in kind, using the Senate, where Republicans are far short of a guillotine-proof majority, as their weapon.

The American constitution is a deliberate mix of checks and balances, reflecting the founders’ fear of enabling a populist demagogue that Democrats see in Trump. At stake is the entire Obama legacy, most notably Obamacare and the post-crash financial regulations on Wall Street, both of which Trump has promised to dismantle.

Maybe he will extend an olive branch by naming a Democrat to his cabinet. Maybe he will even seek an improbable populist front with Sanders – something he mischievously called for more than once on the campaign trail. More probable however is a resumption of trench warfare. And opportunities will abound.

Clinton would have taken office with heavy baggage. Trump’s is as heavy. His businesses, which he refuses to put into a blind trust, raise major conflict-of-interest issues. Later this month the alleged scam at Trump University goes to court. Could a president-elect be called upon to testify? Other shadows in Trump’s past and present could emerge at any time. Fasten your seat belts.