THERESA May’s “deal” is dead. We now need to make clear the best deal is EU membership.

After the last few weeks of drama it is easy to be lose focus. Mrs May’s remarkable achievement of winning a party leadership vote then a vote of confidence while simultaneously heading the first UK Government in history to be found in contempt of Parliament and suffering the biggest-ever defeat is enough to make anyone’s head spin.

So plotting the next few weeks and months will be difficult, but there are a few gravitational forces that cannot be denied. Firstly, the clock is ticking. Unless something else actively happens, the UK and Scotland with it will leave the EU at 11pm (tellingly, it takes effect at midnight Brussels time) on March 29. All this “there’s no majority in the Commons for No Deal” is entirely meaningless, much like the iceberg did not actually bear the Titanic any ill will – exit will happen unless they actively do something to stop it.

Secondly, May’s “deal” is only to exit. The future is dealt with only in an aspirational Political Declaration which is not worthless, but not binding either. So all the bumping of gums by MPs about Norway plus, Canada minus or upside-down Lichtenstein is all so much puff – these negotiations will only start after the exit. If we exit with a deal then a transition period kicks in where EU law will continue to apply as we try to negotiate the future relationship. Basically we’ll have as little idea of the future, except we’ll be outside the EU.

So if Brexit happens, a “soft” Brexit where the UK remains in the single market and the customs union is undoubtedly the least damaging aspiration. This is why the Scottish Government and others have proposed it as a potential “less bad” option in the spirit of trying to find solutions, but they have also been clear EU membership is the best option.

My concern is that there may well be a majority in the House of Commons for a Norway-style aspiration, but that it will be as unsustainable as all the other pipe dreams and in reality offers no stability at all. It would not withstand its first crisis, which would come all the harder because by then we would have lost the chance to avert it, having left the EU.

So let’s take a look at it. EFTA’s own website explains that “the EEA EFTA states have little influence on the decision-making phase on the EU side”. Instead, they focus on “decision shaping”. This involves informal consultations, attendance at some committees, and submission of views in generally short “comments” papers.

This is not nothing, but it is light years from the power we have now in council and the European Parliament, and votes for ministers and the UK’s 73 MEPs.

The term “Vassal State” is overblown and grievously offensive to many EU states who actually were until recently, but the reality is that the amount of influence we would have is really very limited. From day one the deal would be ripe for destabilisation by unsatisfied Brexit ultras and their allies.

The current members of the EEA and EFTA have spent many decades building up how it works; they know the compromises and the shortcomings. The UK political class and administrative machinery are wholly unprepared for the reality that being a rule-taker would bring.

You can imagine the mischief the Brexit ultras would make. In a world where outrage can be whipped up over rules on lightbulbs, kettles and toasters, they’d be braying for vetoes to be used at the slightest hint of a controversial EU law. Of course, they would move on to attacking membership of the EEA on this basis.

Some already see the EEA as a way to gradually move to a hard Brexit by stealth, so even if the arrangement survived first contact it is unlikely it would be remotely stable in the medium to long-term.

It’s a measure of just how damaging Brexit is that the very best alternative is still much worse than EU membership. It still brings considerable economic shocks, has a considerable price tag in terms of ongoing contributions to EU programmes, gives little real extra in terms of control, and reduces our influence in Europe and the world dramatically.

Of the options we face, all of which have significant problems, the best deal remains and always has been EU membership.

Until March, the door remains open to maintaining that and we should not allow ourselves to settle for unstable halfway houses for the lack of a bit of intellectual honesty and political courage.

The reality is that soft Brexit will inevitably become hard Brexit because the Brexit ultras have no desire to compromise. In the face of this the House of Commons only has one real choice: Remain.

Yes, it would be messy and yes, it will take courage, but even the best alternative is far worse.

Alyn Smith is a Scottish politician, and Scottish National Party MEP for Scotland