Former UK prime minister Tony Blair may have another comeback, as the country is now full of questions, and he certainly  has faced a good many jibes over the years, but the most cutting of them came near the end of his 10 years in Downing Street. David Cameron, then the new leader of the opposition and eventual prime minister, declared that Mr Blair’s fresh face had worn off. “You were the future, once,” he said.

The jibe stuck. Worn down by the terrible course of events in Iraq following the US-led invasion of the country in 2003, which the Blair government was a part of, and under pressure from his ambitious colleague and eventual successor, Gordon Brown, Mr Blair could indeed see the end was on the horizon.

Now, time has finally provided a riposte to Mr Cameron following his own much-criticised decision to call a Brexit referendum in 2016, and it is possible to say that Mr Blair should – perhaps even could – be the future again.

There is a prodigious energy to Mr Blair that only seems to defy time. The passion he puts into the international issues he is closely identified with remains unsurpassed. During the coronavirus pandemic, he has gained a whole policy reach on global health resilience. Politico, the American news site, recently dubbed him, in a tongue-in-cheek way, as a “wannabe future prime minister”. It was a joke, but the writer had a point.

Next week, Mr Blair is scheduled to host a two-way chat with John Kerry, the US special envoy for climate, at the Science Museum in London. It will be a reunion of sorts with Mr Kerry. It will also demonstrate how on behalf of the Tony Blair Institute for Global Change, the former prime minister is still engaged at the highest levels – and an example of the kind of thought leadership that Mr Blair has been exerting for years.

Mr Kerry’s energetic return to the spotlight – he is a former senator, presidential candidate and secretary of state – has shown that there is value in expertise and experience.

Mr Blair has never been away. The former Labour party leader has used his connections to build up a formidable body of work on countering religious extremism, disease and pandemic management as well as technological adaptation. He has also worked on improving governance in some of the poorest states.

The only man to have soundly beaten the ruling Conservative party in three consecutive elections has been a figure of ideas since stepping down in 2007. What has changed is that people are listening anew. There is fresh yearning for the leadership style he offers, one of ideas and reassurance. There are three forces at work that are now playing to Mr Blair’s strengths.

Throughout the pandemic, the work sponsored by Mr Blair has provided a framework that recognised the gravity of the threat posed by Covid-19 while offering ways to continue to function.

After electoral defeats under far-left leaders, the Labour party is once again grappling for a winning formula. As the focus groups of alienated former supporters gather, a surprising message is coming out. Why, the respondents ask, did the party give up on Mr Blair’s reformist, progressive agenda?

Thirdly, as this newspaper highlighted last week, the records from his time in government are starting to come into the public domain. A tranche from 1997 showed that he engaged in a detailed quest within his government to test its policy on Saddam Hussein’s rule in Iraq.

A serious charge against Mr Blair has been that he overrode proper process to force the country into the 2003 invasion, which was misconceived and caused immense suffering. In fact, it was the most serious charge. Opposition to the war that ensued and the mishandling of the occupation forced his resignation.