Three days after the EU referendum, I set out in this newspaper my reaction. I made three points. First, put Brexiteers in charge. Secondly, I urged the Government to get on with it. And finally, I said the fight back starts here.

Today, five days after the House of Lords approved the Second Reading of the Brexit Bill, which allows the Government to trigger Article 50, I stand where I stood eight months ago.

The Prime Minister shrewdly placed Boris Johnson, David Davis and Liam Fox in the three leading trenches in the battle to leave Europe. It was in itself controversial and certainly surprising but it was right.

The Prime Minister shrewdly placed Boris Johnson, David Davis and Liam Fox in the three leading trenches in the battle to leave Europe

Any more balanced approach would have opened the door for the charge by the Brexiteers that they were robbed. ‘If only we had been in charge’ would have echoed through the debate as the inevitable compromises emerge from the forthcoming dialogue.

They are in charge. We can all see that they are in charge and they will have to explain why black is sometimes white.

My second preoccupation was to limit – to any possible extent – the damage to our economy that uncertainty over our future relationship with our largest market would cause. Uncertainty is inevitable and will remain so until a clear roadmap is set out in detail and secured by the agreement of both sides. The Lords recognised the mandate delivered by the referendum result and, certainly, its subordinate role as an unelected authority. There was no appetite to assert a more ambitious claim.

They are in charge. We can all see that they are in charge and they will have to explain why black is sometimes white.

I have no time for those who argue the Government should set out its negotiating position in any form in advance of the forthcoming dialogue.

Time and again in private sector negotiations I have set out my demands at the outset. Frequently I never expected to receive them in whole or even in part. It is how negotiation works. You go on until both sides either compromise or give in. Hands are shaken. Optimistic public relation statements issued. But that is not how it works in the public sector. The slightest hint of a defined position becomes a psychological red line.

A more formal position becomes a ‘Maginot Line’ behind which there is no retreat. Immediately one group of supporters will denounce such a position as inadequate by their standards, while the media will define the opening bid as the start line from which any retreat is national humiliation.

Any more balanced approach would have opened the door for the charge by the Brexiteers that they were robbed

The Government knows this full well and has rightly avoided the trap. But the Government doesn’t know what 27 other EU countries will do in the end in their national self interest and to satisfy their parliaments and electorates.

It is more confusing than that. Europe has elections coming up. They don’t even know some of the governments with which they will be negotiating.

The Government needs to proceed as fast as circumstance permits. The scale and complexity of the negotiation make an effective end date impossible to predict. The forthcoming elections in France, Germany and Holland shroud the effective start date in uncertainty. In the end the outcome of Brexit will have to be confirmed by Parliament. It will also have to pass in 27 national European parliaments, several sub-national parliaments and the European Parliament. It was perhaps unwise for our Government to suppose that our Parliament should be excluded where all others were included. Very sensibly, after the Supreme Court interpreted the law, that position was reversed and Parliament was restored to its rightful constitutional role as the ultimate authority.

I will vote in the House of Lords to ensure that position is legally intact. This is not a confrontation with the Government which has already made such a commitment. It is – put simply – a decision to ensure that the Commons has the chance to define its role in the exercise of its authority over what most people regard as the defining issue of our time.

That brings me to my third point. The fightback starts here.

My opponents will argue that the people have spoken, the mandate secured and the future cast. My experience stands against this argument.

I have had my share of opposition politics. I first became an MP in the 1960s when Harold Wilson was Labour Prime Minister. Our duty, we argued, was to oppose. Oppose who? The Government of the day with its popular mandate. From day one we used our parliamentary votes to challenge Bill after Bill despite its clear presence in the Government manifesto.

Of course, we usually lost as the popular elected majority prevailed. But not always. I led the opposition to a Labour Government Bill to nationalise our ports in the 1960s. We so delayed the legislation that it fell when an election intervened.

I led the opposition to another nationalisation measure, the Aircraft and Shipbuilding Industry Bill, which Labour secured only by cheating over the pairing system and celebrated by standing on their parliamentary benches and singing The Red Flag. The rest remains history, as the recent West End play, This House, has revealed.

Only Parliament can legislate. Today it is about to authorise the mandate of last year’s EU referendum. Should that authority have any time limit or be in any way influenced by the outcome of the unpredictable negotiations?

Both questions demand an affirmative answer for me.

At the moment there is no evidence that public opinion has changed since the referendum. The PM rides high in the polls and Jeremy Corbyn’s official Labour Opposition has opted to leave the stage. This reinforces the ‘get on with it’ argument. But what if this present background changes?

The PM rides high in the polls and Jeremy Corbyn’s official Labour Opposition has opted to leave the stage

I have no intention to list the sort of events that could precipitate such a situation. I have never known a future populated by such uncertainty, but my preoccupation is to ensure that if public opinion changes then Parliament has the means to reflect that, whether by election, referendum or rethink.

It should not be forgotten that a month before the EU referendum, Nigel Farage said if the Brexit campaign lost by around 52 to 48 (in the event it won by precisely this margin) it would be considered ‘unfinished business’, with pressure for a second referendum to reverse the result.

And Scotland’s First Minister Nicola Sturgeon has made it clear she is determined to hold a second referendum on Scottish independence if the Brexit talks result in Britain leaving the Single Market.

However, I will make one projection. My belief is that there were two underlying factors at work that led to the referendum result.

The first was the frustration caused by years of stagnant living standards. Something had to be blamed and Europe was readily to hand.

Throw immigration into the mix and the mood for change sought something to latch on to. Nigel Farage articulated that and later Donald Trump’s campaign gave it a transatlantic articulation. Marine Le Pen in France, Geert Wilders in Holland, and Frauke Petry in Germany now contribute a European voice.

The free movement of people enshrined in EU rules is under scrutiny. I think our request for change could find a very different reception on the Continent by the end of the coming cycle of elections.

Parliament must have the chance to react to that.

In the meantime, the Government’s immigration policy could gain increased credibility if it took control of the majority of immigrants, who come from outside the EU and over which the EU has no power to influence us at all. I have to recognise the argument that this could require me to defy a three-line whip by my party. I was first elected to Parliament in 1966 and only on three occasions have I consciously and publicly done that.

The first was when my party whipped against the Labour Party’s anti-discrimination race relations legislation in the late 1960s. I was then involved commercially in hotels and employment agencies. I knew what the disease of ‘no coloureds’ meant. These were the days of Enoch Powell and ‘Rivers of Blood’. I defied the whip and three weeks later my party changed its mind. Around the same time I voted against the Labour Government’s policy to renege on the undertaking to Kenyan Asians at risk of persecution that there would be a home for them here.

I revolted against the Poll Tax. I make no apology – it contributed massively to the destruction of our party in Scotland and would have done so elsewhere in the UK if we had not got rid of it in 1990. My third revolt was a more personal gesture to my old friend, Conservative MP Jill Knight – who entered Parliament with me in 1966 – in her defence of opticians and her family business.

It is an ironic reflection on events that the Tory whip sent to dissuade me from this action crossed the floor and is now a Labour peer!

In the end, politics is a lonely place. There comes a moment when only you can know what you must do. In a sense the public is right. We are only in it for what we can get out of it.

Where they are wrong is in defining the ‘it’ in crude material or financial terms.

The ‘it’ is the knowledge that in some small way we contributed to a wider sense of national purpose and interest.

You can express that in the crudest terms that Donald Trump repeatedly does, or you can draw the inspiration I have derived from every Prime Minister for whom I have worked, who perceived British self interests were enhanced within the shared sovereignty of Europe.