Big ifs continue to surround UK's Rwanda migrant plan

I am writing this in a minibus making its way to Kigali Airport.

Diplomacy comes in many forms. Today it was a day trip to Rwanda.

"The plane is your hotel," said a cheery government official as we stumbled off in a sleepy stupor first thing.

I travelled here on the home secretary's plane as what is known as the broadcast pool reporter - where, in addition to the reports I did for the BBC, I would share my interviews, and our pictures, with ITN and Sky.

James Cleverly had a dozen or so folk in his delegation. Then there were a handful of print journalists.

As I wrote on the way here, Mr Cleverly is the third home secretary to make this journey. Not a single migrant from the UK has yet.

The consistent argument from ministers is that illegal migration poses a colossal, generational challenge.

They add that small boat crossings were increasing hugely, and carrying on as normal wasn't going to be good enough.

So, a novel, eye-catching, controversial idea: sending migrants to Rwanda.

Out of that wreck emerges today's treaty, which attempts to address the court's concerns.

But in my questions to the home secretary, both in a news conference and in an interview, he simply could not be certain all of this effort would pay off.

Such has been the political and psychological commitment to this policy from ministers, that abandoning it would have amounted to surrender.

Instead, there has been extra effort to attempt to make it work.

Some might think our scrutiny unfair.

The development of a novel concept is rarely straightforward: Mr Cleverly acknowledged as much today.

And the setbacks of the last 18 months or so, while easy and reasonable to point out, may seem insignificant if the scheme became workable, and if other countries adopted the same model, as some are considering.

But they are big ifs surrounding a policy that has always hauled around a lot of ifs.

And here's another one. What if Labour win the next general election, as many expect they will?

Labour say they will scrap the project: so where does that leave the Rwandans, as they begin the process of ratifying the treaty here, and making profound legal changes to accommodate the views of a court 4,000 miles away?

There will be more moments around this project, that is a given.

What is not is whether migrants will ever make it here.

As I write this last sentence, I can hear the noise of jet engines through an open door - we are about to fly back.

Scrutiny now turns next to the 43 pages of text.