Coming two days after the prime minister was fined for breaking his own lockdown rules, today’s eye-catching asylum announcement has been greeted by many as a cynical attempt to change the subject.

In reality, this unveiling has been in the offing for a while, with details of the home secretary’s trip to Rwanda pencilled in days before the fixed penalty notices started landing in Downing Street.

What’s more significant is the fact that it’s three weeks until the local elections and we are only just into the “purdah” period where ministers are generally not allowed to announce new policy that might sway voters.

Solutions to thorny issue few and far between

For some time now, Tory insiders have admitted illegal migration and stopping the flow of boats landing on the south coast is one of the biggest political issues they face.

But solutions to this thorny issue have been few and far between.

Co-operation with the French and beefed up security on the other side of the channel has not stopped the arrivals.

Return agreements to send people back to the first safe country they enter have been hard to come by.

Plans to turn boats around in the water were deemed legally dubious and ethically unacceptable.

We’ve even had a flurry of “blue sky” ideas such as wave machines in the Channel and the use of a “passive flotilla” of Royal Navy ships.

After all that, we now arrive at resettling people thousands of miles away in Rwanda.

Policy’s aim is to remove pull-factor of being able to settle in UK

For a start, this will be expensive.

Not only is the UK paying an undisclosed amount for the operational elements of the scheme (estimated by the Refugee Council to be £1.4bn a year), but it has also pledged a separate initial £120m of investment into the economy of the Central African country.

No surprise that one opposition MP has pointed out that it would be cheaper just to put them up in the Ritz.

The primary purpose of the policy is to remove the pull-factor of being able to settle in the UK long term and hence cut the number of people using smugglers to make the crossing in the first place.

That will only work if there is a reasonable expectation that arriving illegally will guarantee you an onward flight to Africa.

We already know there will be exceptions, with extensive briefing that it will be mainly single men who go through the scheme.

The Rwandan government will have the right to reject a person referred onto them as well.

Ministers here will also need to ensure the resettlement process can’t be held up through legal challenge.

Then there is the question about whether this “deterrent message” will really reach those fleeing war or searching for a better life.

‘What is your alternative?’

But today’s announcement is also borne of political necessity and a degree of desperation.

As Boris Johnson said in his speech in Kent: “There is simply no other option and I say to those who would criticise our plan today, we have a plan; what is your alternative?”

This will be the response to criticism in the weeks and months ahead.

Because for all the fury on Twitter, the government believes this is a vote winning policy that will bolster its post-Brexit credentials.

It also has the advantage of forcing Labour in a corner where – in attacking the plan – the party can be painted as weak on the issue.

Of course, success will really be judged by how many go onto build happy lives in Rwanda and whether the number of people attempting the dangerous crossing to the UK drops.

That will not become clear in time for next month’s vote, but it probably will before the coming general election.

The risk for the government is that in its desperation to be seen to do something, it reaches for an expensive but ineffective plan.