I have never met anyone who wishes to exit the EU and not enter into a free trade agreement with the EU to sustain our economic prosperity. And that is the problem.

If we come out of the EU, there might be many unknowns, but one thing is certain: our former EU partners – who we will have just slapped in the face – are not going to give us a better deal than we have now. They could not do this, even if they wanted to, because if they did other countries would follow suit. Contagion.

The best deal we could possibly get is the same as Norway. They get free trade – but they have to pay for it and they have to comply with the rules of the single market, including free movement of people.

So here’s the deal. We vote for Brexit – but still have the same immigration as now, still have to sign up to all the rules, and do not save a single penny piece in contributions. Oh and we don’t get to sit around the table to make the rules any more either. No gain.

Convinced Brexiteers will already be snarling over their Shredded Wheat: ‘The EU needs to trade with us more than we need them, they will still want to sell us their cars and wine!’

Unfortunately the EU does not need us more than we need them. 44 per cent of our exports go into the EU; six per cent of their exports come to us. We sell £21bn a year more in goods and services than we buy from the rest of the EU put together.

There will be no better deal on the table than the one Norway has. It will not save us a penny or tackle immigration. And it will take a long time to negotiate and, in the meantime, there will be grave uncertainty which is bound to impact our economy as uncertainty always does.

But protecting our economic interests is not the only reason I favour Remain.

The world has changed since we had our empire, or even since we joined in 1972. This is now an interconnected, globalised world where each nation is interdependent. Old notions of sovereignty and national freedom have much less meaning than they once did.

Besides, we can elect and remove our own governments very successfully. The vast majority of our law comes from Whitehall and not Brussels. The thought that a UK outside of the EU will have more clout on the world stage to act as we wish is Dixon of Dock Green thinking in a world of Scott and Bailey.

But my commitment to Remain goes deeper still. Nato has helped keep the peace since the Second World War against external enemies, but the EU has played a significant part in building constructive relationships between European powers that have been at war every century for a thousand years. We should not underestimate this or take it for granted. If the UK exits the EU it will hasten its demise. Imagine Europe without some framework of stability? A recipe for future conflict, especially in the Balkans. I do not want my grandchildren called up to fight in another European war.

Many former Soviet bloc countries that wish to move towards EU membership must introduce the rule of law, proper democracy and free market economies. All of this is positive but takes time. The existence of the EU encourages this momentum towards long-term European stability, which is hugely in our national interest.

When a minister in John Major’s government, I attended many Brussels decision-making meetings, headphones on, listening to simultaneous translation. It was slow moving and frustrating. But every time I travelled home I would reflect on Churchill’s great dictum: jaw-jaw is better than war-war.

I am not voting for myself, but for my four smashing grandchildren. It is their future. I firmly believe that they will be better off, stronger and more secure by staying in.