Referendum victory in the bag. David Cameron deposed. Brexiteers in charge of key government departments. And once-remainer PM Theresa May set to deliver a hard Brexit triggering Article 50 before the daffodils next bloom. Whilst the economics of Brexit look increasingly complicated, and the prospect of good trade agreements fanciful, until yesterday the political path to leaving the European Union did look like it could be clear and swift.

That was, of course, before the courts reminded everyone of the most elementary lesson of Britain’s unwritten constitution. The people are not sovereign. We can have referendums forever and a day but they can only ever be advisory. Nor is the Government sovereign. Theresa May may have enormous powers but the British system does not make her omnipotent. No, GCSE Politics lesson number one – Parliament is sovereign.

So to leave the EU, whatever mandate the Government may have from the people, it is Parliament that must trigger Article 50. And suddenly, this makes life much more complicated for the Brexiters. The vast majority of MP’s backed Remain, and whilst most will “respect” the result of the referendum, there are a thousand-and-one ways they can slow matters down and seek clarifications and assurances from the Government about our future relationship with the EU, and the relative hardness or softness of the Brexit. Expect to hear a lot of the Remainers mantra that the Government may have a mandate for Brexit, but it does not have one for hard Brexit.

Once the Bill to trigger Article 50 enters the Lords, expect the Parliamentary ride to get rougher still. Whilst MP’s need to keep a close eye on the views on their Leave supporting voters, the Lords and Ladies have no such constraint. And the Conservatives, of course, have no majority in the Upper House.

The strategy of the Remainers has always been to slow things down. They believe that in 1-2 years time rising food and fuel prices might cause public opinion to swing to believing a great mistake was made on 23 June 2016. Until this week they had no mechanism to try and force the delay they seek. Now they do, and only three months into the job, Theresa May’s life is very very complicated.