There were two big arguments going on in non-party-political politics the past two years: lifting the ban on same-sex marriage (England and Wales, 29th March: Scotland, sometime this autumn after the Commonwealth Games and this other thing: Northern Ireland as soon as they lose the court case).
Making it legal for same-sex couples to marry, matters hugely to people in same-sex relationships, obviously, but to everyone else aside from a small number of seriously homophobic fanatics, it’s no big deal: two-thirds of the population of Scotland agreed that gay marriage should be made legal in a 2012 poll.
This other thing that is happening in Scottish politics: the referendum. In the US, where they have referendums whenever they can get enough voters to sign off on one, they went through a phase of holding referenda in which voters were invited to agree that “marriage is between a man and a woman”, which was then held to mean that marriage between a man and a man, or a man and a woman, was unlawful. In the UK we referend much more rarely, and only – so cynics say – when the government thinks they can get the public to vote the way they want.