ANDREW NEIL: If Donald Trump can rise to this occasion, he'll be truly unstoppable. But can he?

The leaders of Europe woke yesterday morning to a likely prospect most of them find frightening and would rather not contemplate: Donald Trump as the next president of the United States.

They must now plan for upheaval when it comes to American support for Ukraine, backing for Nato, penal tariffs on their exports to the US and whatever surprises the unpredictable Trump has up his sleeve that’s he’s not yet told us about.

The election was already going Trump’s way, as a doddery, confused President Biden’s every public appearance merely confirmed what most Americans had already concluded — that he was unfit to run for re-election — and Democrats had no backbone when it came to doing anything about it.

But Saturday night’s failed assassination attempt at a Trump rally in Pennsylvania makes a victory for The Donald more likely than ever.

Donald Trump pumps a fist at the crowd after a bullet pierced his ear in Pennsylvania yesterday

Donald Trump pumps a fist at the crowd after a bullet pierced his ear in Pennsylvania yesterday

Trump had blood streaming down his cheeks as Secret Service agents put him to the floor

Trump had blood streaming down his cheeks as Secret Service agents put him to the floor 

A number of American friends and sources contacted me overnight to say they thought Trump would now win by a landslide. And these were not supporters of him – they were all Democrats or ‘Never Trump’ Republicans.

Team Biden planned to make liberal use during the campaign of that famous mugshot of Trump taken in a Georgia jail last August after he’d been indicted for racketeering, among other charges, while reminding everybody he was already a convicted felon.

I remember writing at the time something along the lines that it would be the defining image of the presidential election of 2024.

No longer. That accolade now goes to Trump fist-pumping the air, blood splattered across his face, shouting ‘Fight, fight, fight’ as the Secret Service bundled him off the stage after he’d come less than an inch from death. There was even a huge American flag fluttering conveniently in the background.

For Trump and his MAGA (Make America Great Again) movement this will now become the totemic image of his candidacy. It will remind his true believers of the iconic image of US Marines planting a huge flag on a hilltop after the brutal battle to take the island of Iwo Jima from the Japanese in early 1945.

But that famous photograph involved an element of staging (a smaller flag had previously been raised on the site). Trump’s potent picture is entirely authentic. Nobody can dismiss it as fake news.

The core theme of the Biden campaign, one that is heavily promoted by its many cheerleaders in the media, is that Trump is an existential threat to democracy. It’s typical of the overheated rhetoric that now dominates debate on both sides of the political divide in America these days.

But it will be rather harder to credibly deploy that line against a political candidate who came so close to losing his life campaigning in a democratic contest.

The shooting (in which, let us not forget, one person was killed and two seriously injured) has led to predictable calls for America to curb its hateful and hostile political discourse, in much the same way as Labour MP Jo Cox’s murder during the Brexit referendum in 2016 produced pleas for a more civilised debate in our politics.

I suspect such calls will be even less successful in America than they have been in Britain.

President Biden and his Democratic predecessor in the White House, Barack Obama, were quick to condemn ‘political violence’, though their remarks were perfunctory and lacking any genuine outrage. Curiously, neither could bring themselves to use the words which would have properly described what had happened — an attempted assassination.

Far from cooling it, America is already awash with mad conspiracy theories, fuelled by the incompetence of those meant to protect Trump in allowing a 20-year-old with a semi-automatic rifle to gain access to a rooftop overlooking the rally.

The shooting has led to predictable calls for America to curb its hateful and hostile political discourse, writes ANDREW NEIL

The shooting has led to predictable calls for America to curb its hateful and hostile political discourse, writes ANDREW NEIL

The Secret Service¿s chaotic efforts to evacuate Trump after the shooting only added to a loss of confidence

The Secret Service’s chaotic efforts to evacuate Trump after the shooting only added to a loss of confidence

Their ineptitude was highlighted in a remarkable BBC TV interview that ran across America’s broadcast networks, in which one witness said he’d warned the police and security operatives that there was a shooter on a nearby roof. The Secret Service’s chaotic efforts to evacuate Trump after the shooting only added to a loss of confidence.

This is being taken by the conspiracy theorists as proof that it was all a deep-state effort involving the FBI and the Secret Service to eliminate Trump (the MAGA camp’s take) or that it was all staged by MAGA operatives to boost Trump’s election chances (the nutty Left’s take).

Such nonsense does not deserve the time of day. But the Secret Service and its associated law enforcement agencies are in for a terrible reckoning. There are already calls for its director to resign.

Biden will be relieved that his unfitness to run again is no longer dominating the headlines. But it is temporary relief. The pressure to find a candidate who could beat Trump is more urgent than ever, though it may be that he is now unassailable no matter who the Democrats put up as a candidate.

Indeed, some Democratic hopefuls might think it wiser to sit out this particular presidential election cycle. After Saturday night, the Democrats look like they’ve run out of good choices.

And the clock is ticking. The Democratic convention is only five weeks away and, unless the ‘Dump Biden’ rebels move quickly within the next 10 days, they will run out of time to make the necessary arrangements to turn Chicago into an ‘open convention’ beauty parade of alternative candidates.

Police stand over the body of alleged shooter Thomas Matthews Crooks

Police stand over the body of alleged shooter Thomas Matthews Crooks

Biden would simply be confirmed as the candidate by default, since most of the delegates are pledged to him and can only be released if he drops out. A few days ago Biden said: ‘It’s time to put Trump in the bullseye,’ confirming that his capacity for gaffes is unlimited.

As the leaders of America’s allies — and enemies — get to grips with the implications of a Trump presidency, all eyes will be on the Republican convention under way from tomorrow in Milwaukee.

It was always going to be an uncontested coronation for Trump. Now it will be an emotionally charged, historic event designed to propel him remorselessly to the White House and watched not just by America but by the world.

Back in 1984, I was in the hotel next to the Grand in Brighton for the annual Tory conference the night the IRA blew it up in a failed attempt to assassinate Margaret Thatcher.

She insisted on addressing the conference first thing that morning, even though she had almost been murdered and had had to be evacuated in the middle of the night to a safe base.

By the time we gathered in the conference hall, we had been joined by all the London correspondents of the world’s media. The Iron Lady arrived on time to a sober but warm and heartfelt reception.

She spoke with calm authority, no bitterness, no tub-thumping, just an unbending resolve to defend democracy. It was the speech of the leader of a proud nation, not the leader of a party.

If Trump can similarly rise to the occasion in Milwaukee then he really will be unstoppable in November. If he succumbs to anger, exacerbates division and makes ridiculous accusations against Democrats then he might just still be vulnerable.

In 1912, another presidential candidate, Teddy Roosevelt, spoke in Milwaukee. Like Trump he had barely started his stump speech when he too was the target of an assassin’s bullet, which lodged in his chest. But Roosevelt was a toughie — once boasting he felt as strong as a bull moose — and decided he’d finish his speech, which was 84 minutes long.

Also like Trump, Roosevelt had already been a Republican president. But he was now leading a breakaway party called, appropriately enough, the Bull Moose party. Third parties never win in America. Trump’s test this week is somewhat less onerous.

The bullet only grazed his right ear and he still leads the Republicans. It looks as if only his own darker demons can stop him from being the next president of the United States.

So far, in the aftermath of the shooting, he’s remained remarkably restrained. He needs to stay that way even in front of his adoring faithful in Milwaukee, for whom he is now a living MAGA martyr.