I’m feeling sunny and optimistic. Let’s assume the question doesn’t get bogged down by the courts or by politics, that the Yes campaign is genuinely cross-party and no-party, that the public will get a chance to write the first constitution for an independent Scotland at some point, and that the referendum succeeds by a clear margin.

The SNP will, on this happy day, have achieved their objective. Admittedly it’s in some ways a simpler objective than any other party – Scotland is either independent or not – but it’d be an extraordinary achievement for a party which in 2003 looked a long way from government, and as recently as the 1980s looked a whole lot further away still.

So what happens next, both for the SNP and for individual SNP members and politicians? Here are some options.

Retire happy. At least one of the SNP’s younger MSPs I know will take this route. Job done. It baffles me that anyone wouldn’t have other political priorities, but it’s consistent. And it certainly makes sense for the older generation. Salmond’s not old by political standards – he’ll turn sixty just after the vote – but it would be a strong point to choose to stand down, and one way to disprove the adage that all political careers end in failure.

Attempt to become Scotland’s answer to the ANC. Sure, the ANC’s struggle was harder to say the least – the Maximum Eck never spent a day in Saughton for political crimes – but parties that fulfil their purpose and deliver radical constitutional change do sometimes try to stay together and stay in power thereafter. The game here is to become the new establishment, but, typically, this way corruption lies.

Join other parties. It’s not hard to see how this might work. The SNP span more or less the whole political spectrum at Holyrood, and they’re held together by a love of winning (no bad thing in a party) plus their primary purpose. Once independence has proved itself to be the settled will of the Scottish people, those who want to stay in politics would surely want to find more consistent ideological bedfellows. This could only happen once the three pro-union parties accept the result and move on. So at that point why wouldn’t Fergus Ewing, John Mason or even John Swinney join a Murdo-esque post-Tory Tories? Might Marco Biagi or Linda Fabiani go Green? Would the soft left of the SNP really not want to work with the Labour types they tend to agree with on non-constitutional matters? If a Lib Dem party still exists at that point, perhaps Michael Russell could lead it? (no offence Michael)  edit: I can see now I was wrong about this one 😉

Split into new parties. Obviously this can be combined with the option above. Across Europe party mergers, divorces, and realignments are ten-a-penny. It may not be clear what the empty space looks like, ideologically, but why might we not see something new here?

The membership is another matter. We certainly get plenty of comments here on Better Nation that start “I’m an SNP member now, but post independence I’ll be a.. ” and which typically end “Green” or “Socialist”. Many SNP activists see the party and the government as a means to this single end: they may campaign to elect a local MSP who they rate, but the purpose of that MSP is to vote for the referendum legislation, so that an independent Scotland can be more (insert other objectives here). Do they stay, or if not, where do they go?

The other most interesting question about the SNP’s post-referendum future is where do the brightest and best of the younger generation go, notably future FM candidates like Nicola and Humza? My guess is that both will want to hold the party together and hold onto office, but the membership and leadership have divergent ideologies which could well make that hard. Still, it’s not a bad dilemma to have. And I look forward to a politics where the debates are primarily about an independent Scotland’s economy, social policy, civil liberties and environment, not the constitution. That will be progress.