CNN  — 

At the end of the worst day in his professional life, many in the UK are asking: How long can the British Prime Minister stay in his job?

It’s a reasonable question to ask of the British Prime Minister. The man who can barely go a week without suffering some kind of stunning political setback faced his most public embarrassment on Tuesday, as the UK’s highest court ruled that his decision to unilaterally suspend Parliament was unlawful. Worse, he might have misled the Queen in doing so.

Under normal circumstances, you’d expect a leader so under fire to realize their time was up. But Brexit has created some pretty abnormal circumstances in Westminster.

How long can things go on like this? That really comes down to whether or not Johnson or his opposite number, Labour leader Jeremy Corbyn, have the guts to take action that will ultimately lead to a general election.

Corbyn was buoyant at his party’s annual conference in Brighton – not least because the Supreme Court ruling eclipsed three days of bitter infighting that had dominated headlines in the UK.

In a hastily rewritten keynote speech, Corbyn demanded Johnson resign and said his party was ready to trounce the Conservative party in a general election.

But in truth, Corbyn is trapped, with no way of triggering an election on his terms. Ordinarily, you would expect an opposition leader, confronted with a weak and floundering Prime Minister, to schedule a vote of no confidence. In theory, that could happen as soon as this week.

uk supreme court
UK Supreme Court rules Parliament suspension unlawful
01:34 - Source: CNN

However, the constitutional process that follows could allow Johnson to sit out the October 31 Brexit deadline and have the UK leave without a negotiated deal – something Corbyn has pledged to avoid.

Some Labour sources believe that in this scenario, they would be able to work with the speaker of the House of Commons, John Bercow, to remove Johnson from power and secure the extension. But it’s far from clear that this would be possible, legally or constitutionally.

Corbyn’s other option is to sit tight. Labour believes that it can pile enough political pressure on Johnson that he resigns and forces the “coming election,” as Corbyn described it in his Tuesday speech.

For his part, the Prime Minister is also trapped. He has no majority to pass a Brexit deal, no support to call an early election on his own terms and has been forced to sit and watch his opponents in Parliament wreck his Brexit agenda. Most recently, they passed a law instructing him to request a Brexit extension. Johnson has said that he will obey the law, but that Brexit will not be delayed.

In the short term, Johnson appears to have only two options. He could resign as PM, let Corbyn and his anti-no deal friends work out how to request the Brexit extension, then wait for the inevitable election that would follow.

In that scenario, Johnson could point at his opponents, call them Brexit wreckers and hope that his Parliament-versus-the-people message works enough to win a fresh majority.

The risk here is that Johnson hits the campaign trail looking like a weak leader who let Brexit slip through his fingers. If he gets it wrong, he could suffer the double indignity of being the shortest-serving British Prime Minister ever and be condemned as a worse failure than even his predecessor, Theresa May.

Or, like Corbyn, could also sit tight. But that risks the un-suspended Parliament taking control of government business and tying him up in even more anti-Brexit legislation.

Right now, both men sincerely believe that they can trounce the other in an election. And that election will be ugly. Both men are already taking brutally hard lines against one another.

On Tuesday, Corbyn talked up Johnson’s willingness to strike a post-Brexit deal with Trump’s America: “A No Deal Brexit is really a Trump Deal Brexit… It would be handing our country’s future to the US president and his America First policy.” Trump is not popular in the UK, and this message resonates especially well with those who oppose Brexit. Corbyn also painted Johnson as a friend of the super-rich, rather than ordinary people: “He is part of an elite that disdains democracy… He is not fit to be prime minister.”

Yet as loud as Corbyn’s fans cheer, Johnson’s poll ratings remain stronger than you might think. A man who has misled the Queen, is a friend of the bankers and has the backing of a man as unpopular as Trump still enjoys a healthy poll lead over the leader of the opposition, which is very unusual when you consider that Corbyn’s Labour party has been out of power for nearly a decade.

Corbyn has his own electability problems. As one Conservative source told CNN last week: “He’s just an easy target, isn’t he? Anything you say about him being hard left or confused on Brexit or dodgy associations has the added benefit of being true … Like Trump, there’s always a tweet.”

However, the Conservatives would do well to remember that Corbyn is at his best when out on the campaign trail. In 2017, May thought she could call a snap election and win a majority of over 100 seats. Corbyn outperformed against expectation and took her majority.

The UK is frozen in time, despite the fact that time is running out. The leadership of both parties believe that if an election is held on their terms, they can blow the other out the water. The problem is, neither leader has a clear path to securing an election on their own terms.

So how long will Johnson remain in power? As long as neither he nor Corbyn is willing to take a leap into the unknown.