The Ulster election

Britain's bold initiative toward self-government in Northern Ireland has brought unexpected as well as expected difficulties to the surface. But these can be overcome as more and more of the Northern Irish emulate those among them who refuse to take intransigent positions. And as Britain shows that it intends to follow through sensitively and firmly in the spirit of James Prior's assurance: ''We have got to persevere, and we don't give up just because a few people say they are not going to take part (in the assembly for which elections were held last week) or because others say it won't work.''

The resources of the people were suggested in a recent interview by the new Roman Catholic Bishop in Belfast, Cahal Daly, who was installed on Sunday. In answer to a question on whether terrorism was leading to civil war, he said: ''The worst predictions have not been fulfilled. If one looks at how many beleaguered communities, riddled with violence, have nevertheless kept their essential social stability and inherent goodness, it is a great tribute to the people.''

By the same token the worst predictions about the new assembly need not be fulfilled. Here Britain can help, as suggested before the elections, by considering the views even of those who stay out of their seats.

The whole idea is to find step-by-step agreement between the divided political/religious communities on measures for self-rule If no start is made no conclusions can be reached. The burden is great both on representatives of the Protestant majority who would use the assembly to lock in unfair advantages - and on those of the Catholic minority who would use their boycott of the assembly to prevent all compromise.

Not surprisingly almost two-thirds of the assembly's 78 seats went to Protestant unionists. Encouragingly, a few more seats went to the more moderate of the two major unionist parties. And the conciliatory, nonsectarian Alliance Party got 10 seats.

The main surprise, and an unpleasant one, came on the Roman Catholic side. The moderate Social Democratic and Labor Party (SDLP) won 14 seats but lost others to the radical Sinn Fein, the political wing of the outlawed Provisional Irish Republican Army. Sinn Fein wound up with five seats and 10 percent of the electorate.

The depth of the challenge is clear when such support goes to a group campaigning on the unconscionable slogan ''A ballot in one hand and a gun in the other.'' Some saw it in part as due to Prime Minister Thatcher's unyielding response to the hunger strike that resulted in the death of 10 IRA prisoners. Hard-line Catholic reaction to British mishandling of the political and economic situation in Northern Ireland was cited by John Hume, the SDLP leader whom the British regard as a responsible politician. He also cited reaction to unionist intransigence in trying to dominate the governmental process.

There is obviously plenty to negotiate among the Northern Irish and between them and Westminster. The assembly is an inch in the ''keep trying'' process which Mr. Prior, Britain's secretary of state for Northern Ireland, rightly says is owed to the people.

Concentration on getting it going should not foreclose those discussions between Britain and the Irish Republic - the third point of the Irish triangle - which reached such a promising stage a year ago. The framework has remained, though there has been a chill in the air lately. The possibility of a parliamentary-level body - drawn from the Irish, British, and European parliaments, as well as a Northern Ireland assembly - is still on the books. Such a prospect is one more reason to give the new assembly a chance.