LAST week, California Democrat Nancy Pelosi – the majority leader in the House of Representatives – announced that she was launching an official impeachment inquiry intoDonald Trump.

Pelosi’s inquiry will bring the six congressional committee investigations currently ongoing into Trump’s conduct together under one umbrella — with the aim of establishing whether or not the president committed a federal crime and should, therefore, be removed from office.

Pelosi has long resisted calls for Trump’s impeachment. Alongside other top Democrats, she believes an attack on the legitimacy of his presidency, led by Congress, could reinvigorate the GOP’s right-wing base just in time for the 2020 presidential election. But recent revelations have forced her hand.

A few days ago, it was revealed that during a phone conversation in July with Ukrainian President Volodymyr Zelensky, Trump offered to release millions of dollars’ worth of military aid to Kiev if Zelensky could dig up some dirt on Hunter Biden’s business dealings with a Ukrainian energy company.

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Hunter Biden, of course, is the second son of former vice-president and Democratic presidential frontrunner Joe.

A transcript of the conversation published by the White House confirms that this conversation took place and that Trump did indeed try to arrange a quid pro quo with Zelensky.

Trump, to be fair, has barely even tried to deny the story — although he has, in typically understated fashion, denounced talk of impeachment as “the greatest scam in the history of American politics”.

The Zelensky scandal was the final straw for Pelosi.

To the neutral observer, it very much looks like Trump was encouraging a foreign power to intervene in America’s domestic political life in advance of a crucial re-election fight.

And if he was, then Pelosi wouldn’t be doing her job as an opposition leader if she didn’t initiate impeachment proceedings.

The National: Democratic Speaker Nancy Pelosi initiated impeachment proceedings against the PresidentDemocratic Speaker Nancy Pelosi initiated impeachment proceedings against the President

Senior Democrats welcomed Pelosi’s decision. “There are some things that are bigger than politics,” Massachusetts Senator and Democratic primary candidate Elizabeth Warren said on Wednesday.

“I took an oath of office, and that oath was to follow the constitution. No one is above the law, not even the President of the United States.”

The legacy media voiced its support, too.

“The Ukraine scenario is simple and [goes] to the heart of Trump’s powers as commander-in-chief,” commentator Jennifer Rubin wrote in the Washington Post on Thursday.

“By picking the right fight at the right time, Pelosi has positioned [Democratic lawmakers] to make the best possible case against Trump.”

And yet, Democrats should think carefully about how this scenario is likely to play out — because it won’t necessarily work to their benefit.

Trump is now the fourth US president to face a formal impeachment challenge.

The first was Andrew Johnson in 1868, the second was Richard Nixon in 1974 and the third was Bill Clinton in 1998.

But only Johnson and Clinton were actually impeached by the House — Nixon resigned before the process could be completed.

And even then, both Johnson and Clinton were rescued by the Senate, which has to vote by a two-thirds majority, and after a heavily politicised “trial”, in favour of ending the incumbent president’s term.

Given the Republicans currently hold an eight-seat advantage in the Senate – and that the congressional GOP is unshakeably loyal to the White House – the odds on Trump losing the overarching impeachment battle seem extremely thin.

More to the point, however, what would Democrats actually achieve by getting rid of Trump before November 2020?

Seeing the man who defeated Hillary Clinton carted off in disgrace would no doubt be cathartic for the party, which remains wounded and divided in the wake of the 2016 result.

But at the same time, Trump is, in many ways, an ideal election opponent, much less politically savvy than his vice-president, Mike Pence — who would almost certainly replace him as head of the GOP if impeachment went ahead — and temperamental to the point of self-destruction.

His poll numbers tell their own story. According to a survey conducted in mid-September, before the Zelensky scandal erupted, Trump would lose in a head-to-head contest with Joe Biden by 14 points, with Bernie Sanders by eight points and with Elizabeth Warren by six points.

Sixty per cent of Americans say Trump doesn’t deserve a second term. And 65 per cent of American women say they disapprove of Trump’s record as president.

As long as the Democrats nominate one of their front-tier candidates, they have a decent chance of recapturing the Oval Office next year.

But this brings us back to Pelosi’s initial misgivings about the political fallout from an impeachment drive.

TRUMP supporters are already fuelled by a powerful sense of grievance against what they see as the “Washington elite”, and against a political system they believe is rigged against their values and interests.

By deploying a rarely used constitutional mechanism to bar Trump from standing in 2020 — rather than simply standing against him and winning — the Democrats risk consolidating the GOP’s core vote.

Moreover, impeachment would feed into the comforting but illusory liberal narrative that Trump’s election three years ago was an aberration; a moment of collective madness from which the country will soon naturally recover.

But it wasn’t – and Democrats need to acknowledge that if they’re going to avoid falling into the same pattern of complacency that sealed Clinton’s fate in 2016.

Trump has been sustained in office by three things.

The entrenched racism of America’s white majority, to which he has consistently appealed.

A powerful network of conservative media organisations, which has consistently amplified his appeal.

And the Republican party itself, which could have pulled the plug on his presidency at any time but has chosen instead to back him through every major controversy, no matter how extreme.

And herein lies the problem for the Democrats: even if they manage to get Trump impeached, the structures of power that launched him into the White House in the first place – right-wing voters, the corporate-nationalist media and the GOP – aren’t going anywhere anytime soon.

In other words, being tough on Trump and tough on the causes of Trumpism are two very different things.

The alternative Democratic strategy is clear: the party needs to destroy Trump politically by reminding his supporters, and the US electorate at large, of what a fraud he is.

In 2016, Trump stormed Washington promising to “drain the swamp”. Three years into his presidency, he has one major legislative achievement to his name – a massive tax cut for the ultra-rich – and a pile of corruption allegations mounting at his door.

Before he took office, Trump railed against the “handful of large corporations” that had “stripped [America] of its wealth”; after he took office, he systematically deregulated the US economy and presided over a boom in executive pay.

His plan was never subtle: by presenting himself as a champion of ordinary, hardscrabble Americans, he would free himself up to implement a bespoke economic agenda for the 1%.

Which is precisely what he’s done.

Federal data released this week shows that income inequality in the US has reached its highest level in five decades.

US consumer debt is now higher than it was before the 2008 financial crisis.

Healthcare costs are rising year on year, particularly for retirees and people with pre-existing conditions.

These are the issues that should form the basis of the Democrats’ general election pitch, not pedantic moralising about Trump’s character.

It’s easy to forget this now, because he secured the presidency on an electoral college technicality, but Trump won 63 million votes in 2016 — and that was after he’d mocked a disabled reporter, attacked the judiciary and been credibly accused, on multiple occasions, of sexual assault.

Americans tempted to vote for Trump a second time around won’t be dissuaded from doing so by a congressional impeachment hearing.

That doesn’t mean Pelosi is wrong to begin the impeachment process.

The American public deserves to know whether or not their president, the commander-in-chief, broke the law.

But even if he has, a distressingly large chunk of US society will simply shrug it off. If Democrats want to bring an end to the Trump era, they have to confront the forces that made Trump possible.

They can only do that out in the political open, during a hard-fought general election campaign – not behind the doors of a committee room in Washington.