This sounds like yet another attempt to punch a hole in taxpayer cash below which the corporate blob can drink a deep fill.
The sheer logistics of invading Britain mean there is only one way it can be done. All else is froth. Any invader will have to capture and neutralise the government. That's all they have ever had to do. And it's worked twice in the last 1000 years.
Britain is hardly going to be suddenly surprised by 1,000,000 troops that appear from nowhere.
Also, as we know, it's cheaper to buy British infrastructure and run it into the ground than boots on the ground.