For nearly a year now, we have been cautious — even indulgent — when it comes to criticizing the way political leaders are handling this exceptional pandemic with the malicious whims that come with a novel virus. But whether we like it or not, the scale of this crisis also serves as an incomparable tool for measuring the leadership skills of any given head of state or government.

Most observers now agree that Donald Trump's casual handling of the pandemic probably cost him his reelection. And now, another prominent leader is coming under fire for adding chaos upon the chaos. We will remember for a long time the pictures of British or foreign travelers rushing this weekend to the stations to try to escape London where a new lockdown was introduced without warning on Saturday night. Only a few, including in his own party, still defend Prime Minister Boris Johnson who seems once again to be indecisive and inconsistent.

If it turns out that his country's health services have been truly aware of the new strain of the virus for a week, then it will be very difficult for Johnson to justify the measures to loosen restrictions that he initially wanted to authorize for the Christmas holidays.

The accusations mounting against the prime minister, including within his Conservative party, include the worst charges that can be brought against a politician: nonchalance. We saw evidence of it when he advised British citizens last March to "sing Happy Birthday twice while washing your hands" to protect from the virus before deciding, belatedly, to implement a lockdown like virtually every other Western country.

He's been driven by opportunism rather than conviction ever since he was put in charge.

We saw the same kind of nonchalance last Wednesday when he told Parliament that it would be "inhuman" to cancel Christmas, even though he had no alternative solution. Finally, Johnson's casual leadership style is on display just as he is called on to lead his country out of the Europe Union at the very moment when — like those same European neighbors — a health crisis is deepening yet again.

The short-circuiting between two major events, Brexit and the pandemic, is probably what will come with the steepest political price. Driven by opportunism rather than conviction ever since he was put in charge of the country, Johnson has indeed benefited from a good dose of indulgence from the general public that had perhaps fallen under the spell of his eccentric leadership style.

But times are changing. Today, amateurism and a blatant inability to face the job of making unpopular decisions are all that is left.

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