The politics of peace have a powerful resonance in the Northern nationalist community, judging by the record levels of support for Sinn Fein and the SDLP in the Assembly elections.

It is a community long demonised in many quarters as almost preferring a state of war and conflict. The attempt to marginalise Northern nationalism has proved itself to be the great political cul-de-sac of the last quarter of the 20th century in Ireland.

The vote for the agreement, and now the vote to work the Assembly, were as close to unanimous among nationalists as made no difference. By any criteria that is an overwhelming vote for peaceful change.

There are some who are finding it hard to cope with this new dispensation among nationalists, and who long for the old days of lead-pipe certainties about alleged nationalist proclivities.

Cognitive dissonance is a condition where, all objective evidence considered, you know you have been wrong in your assessment of a situation, but you somehow continue to insist that you are right.

It is time, in the wake of this massive vote for the peace agreement twice in a little over a month in the nationalist community, for those who have spent the last quarter-century demonising Northern nationalists to finally admit they have got it totally wrong.

It is hard for such commentators and pundits to acknowledge that much of their life work, in seeking to perpetuate a state of affairs in Northern Ireland where the underlying reality remained unionist hegemony despite some cosmetic changes, has been an utter failure.

Nationalists, through John Hume and Gerry Adams, have changed the state irrevocably by their simple decision to work together on a peace process. By so doing they have for ever ended the marginalisation of their community. They have also succeeded in elevating the nationalist contention that the pursuit of a united Ireland is as legitimate a political objective as the continuation of the Union.

Commentators and politicians who rush to call on the IRA to announce that the war is over should equally ask Ulster unionists - specifically Paisley, McCartney and Trimble - if they accept that the peaceful pursuit of a united Ireland is as legitimate a goal as the continuation of the Union. Unionists have yet to concede that fundamental point.

The understandable fears among unionists of a renewed IRA campaign are mirrored on the nationalist side by the belief that their aspirations will never be given equal weight in the Northern state.

Thus I have already heard fears expressed, in the aftermath of Trimble's poor showing, that nationalists will come under pressure to give more, or not pursue as strongly their own objectives in the new Assembly. There is no doubt that unionism is convulsed by this new politics of peace. It is the irreducible law of politics in Northern Ireland that once one side is relatively united as nationalists are, then it becomes disjointed on the other side.

The "Poor David" scenario, where nationalists must form a rescue mission to save the Ulster Unionist leader, has already taken hold in some media quarters. To put it bluntly, nationalist leaders cannot save David Trimble by insisting any less on the cross-Border institutions or equality agenda which is at the core of the peace agreement. Indeed, if they were to do so they would seriously compromise their standing with their own community which could have grave consequences for voter confidence in them.

David Trimble signed his political legacy when he agreed to the Good Friday document. What he actually requires now is a larger dollop of the political courage of Hume and Adams who both transformed their parties' thinking, while taking great political risks in so doing.

He will have to end his one-trick-pony show of blaming Sinn Fein for every real and imagined problem with the agreement. He will instead have to condition his followers to the reality that a new political discourse has taken hold in which the old certainties no longer apply.

In his task Trimble is helped by the remarkable drafting of the agreement document which has appeared to anticipate almost every major objection to its operation and which, for instance, has rewarded Trimble now with more seats than his share of first-preference votes indicated.

In an election where parties with strong positions on the agreement for or against were rewarded on the first count, the provision for the election to be held under the most extensive proportional representation rules may well have saved Trimble's career.

The latest election also shows that this new, confident nationalism has now become a smooth operator of the new political dispensation brought about by the peace process. Their voters now know that their inclusion in the process appears to present the greatest threat to their opponents.

On a recent visit to Belfast I found that the only major worry the Sinn Fein leadership had about the election was that some of their wavering supporters would not turn out as a silent protest against the peace process.

Abstentionism, after all, is a natural tool of Northern nationalists. The fact that a record number voted for republican candidates is an indication of how far their political thinking has progressed. A generation ago John Hume and others marched to bring about the most basic political reforms, such as one-man-one-vote. The same man, and other nationalist and republican leaders, will now transform the entire system from the inside once the Assembly begins.

It is a change stunning in its audacity, the exact opposite of how the state was governed for all of its existence to date. Reality has truly been turned on its head in the last few dizzying years, and it is little wonder that we are all still running to catch up with the new vista.

Niall O'Dowd is founding publisher of the Irish Voice