That's highly likey to happen, and anarchists have, and will, safeguard the revolution. To think the ruling class will be swept away in one big revolution is just not logical. A process of revolution, with varible results and varible ideology will take place. The advantage of anarchist theory is that it's not black and white or dogmatic, meaning the ability to adhere to conditions, rather than some strict ideology. Again, through Federation, the problems of each situation could be dealt with.

Anarchist ideas such as the freedom of association means exactly that, as long as it does not impede on anyone else's others freedom. If any minority such as the one you describe came about, and cut into others freedoms or the progress of social change, then it would be countered. These gains will be defended, not by the new 'party', but by the people themselves. When workers and communities are directly involved in real, sweeping change, it is more likely their interests will be defended, as it would mean the loss — not only of some vague idea of 'the workers state', or political emancipation — but of their very livelyhood. We've seen this happen in the Ukraine in the period of the Russian Revolution, with the formation of a People's Militia, and again in other times throughout history.

Again, the difference between anarchist and marxist systems mainly deal with means and methods used, and the issue of power. The idea that anarchists would be less vigourous in safeguarding social change is simply wrong.

Cheers

Jared D