Theresa May's Great Repeal Act is not symbolic - it's vital for British sovereignty

Well, folks, you have your answer. Britain will begin the formal process of disengaging from the European Union before the end of March. Barring a unanimous decision by all 28 states to extend the talks, the UK will become a fully sovereign country in the first quarter of 2019.

Many of the people who have been dancing up and down demanding a timetable will now immediately switch to demanding precise details of the government's negotiating position. Will it be a hard Brexit or a soft Brexit? Will we stay in parts of the customs union? How much will we limit migration from the rest of the EU? How many existing EU regulations will we keep on our statute books?

These are important questions, but the PM would be a fool to answer them in interviews with British journalists. She has a long negotiation before her. The one thing she has rightly made clear is that Britain will repeal the 1972 European Communities Act – the statute that provides for EU law to have primacy over British law.

Grant that and everything else follows. We might replicate some of our EU obligations through bilateral treaties. We might remain in some of the EU's research and educational programmes and, if we do, everyone accepts that we'd continue to pay our share of the costs. We might retain arrangements that provide for reciprocal rights to work and study.

The difference is that, from now on, we'll be entering into those deals as an autonomous country. There will no longer be a mechanism to impose rules on Britain without the consent of our elected representatives. Whatever relationship we have with our neighbours, it will be based on cooperation not coercion, alliance not assimilation.

There will no longer be a mechanism to impose rules on Britain without the consent of our elected representatives.

Don't make the mistake of thinking that scrapping the 1972 Act is chiefly symbolic. That piece of legislation means that any EU ruling, however bizarre, however at odds with the plain text of the treaties, is automatically incorporated into British law. Our courts uphold EU regulations without needing an implementing decision by parliament. Indeed, if parliament explicitly legislates in a contrary way, our judges will swat its vote aside and give precedence to the Euro-ruling. As long as the European Communities Act is on the statute books, the sovereignty of parliament, which we fought a civil war and deposed two kings to assert, is in abeyance.

Once the 1972 Act has gone, we should want the closest and most cordial of associations with our partners. Think of the relationship between Canada and the US. The former has a federal state on its doorstep with nearly 10 times its population. It enjoys the tightest relationship imaginable with that federation in terms of defence, diplomacy, commerce and, indeed, mutual civil entitlements. But it is not part of the federation. A Canadian MP or judge cannot be overruled by a higher authority in the way that a state legislator or judge in, say, Idaho can be.

If we want such an outcome from the talks, we need to use the next six months wisely.

If we want such an outcome from the talks, we need to use the next six months wisely. First, we must ensure that we have alternative trading arrangements lined up with friends on other continents. Although there is every reason to be hopeful about the substance of our EU talks, it would be mad to go into them without a fall-back position: that was David Cameron's mistake in the renegotiation.

At the same time, we should talk to our European allies about getting a looser deal that benefits both sides. We are plainly not going to relate to the EU 27 simply as a benign third country like, say, South Korea. Some of our existing institutional and structural links will remain in place. Guy Verhofstadt, the European Parliament negotiator, has called for a form of "associate membership" for Britain that might also be offered to the EFTA countries. The German Europe Minister, Michael Roth, has mentioned something similar. Such an outcome is, in truth, the only fair-minded way to interpret a 52-48 vote. Britain voted to recover powers from Brussels, not to sever all ties.

Whatever the eventual deal, though, the chief grievance of Eurosceptics has been addressed. The UK will be, once again, a fully independent country. Brexit means Brexit.