There is a deep sense of foreboding about the future of Northern Ireland as the new economic envoy from the U.S., Declan Kelly, ends his first round of meetings with the leaders of the government there.

Overnight violence in Lurgan where three men were jailed Thursday for dissident IRA activities was just the latest in a series of violent incidents that have undermined the work of the peace process.

Last week a 600 lb bomb was discovered near the Irish border with the Republic while attempts to kill an off-duty policeman in Derry failed.

Dissident IRA groups are desperate to derail the power-sharing government and know they need to pull off a spectacular bombing if they are to do so. Security experts say there have been many close calls and it may only be a matter of time.

Though the rest of the world has looked away from Northern Ireland thinking the problem solved the reality remains that there are still miles to go before the peace process is finally secure.

Dissident threats and a looming political crisis for unionism are the major shadows hanging over more political progress.

But perhaps even more serious is a developing political stalemate brought about by a scenario that could see Sinn Fein take over as the largest party in Northern Ireland in 2011.

The Assembly elections are set for spring of that year with Sinn Fein holding a huge advantage over the SDLP in the nationalist vote. The unionist vote is far more evenly split.

In that scenario the extraordinary vista of a Sinn Fein First Minister, essentially prime minister of Northern Ireland emerges.

The peace accords are clear that the party receiving the largest vote elects the First Minster. Although the nationalist vote is smaller by a 55-45 ratio, the fact that Sinn Fein will overwhelmingly win it means the party may well have enough votes to take the top job in Northern Ireland politics.

That has set the cat among the pigeons for the Democratic Unionist Party leader Peter Robinson who knows well that he will have great difficulty sustaining power if Sinn Fein end ups in the top seat.

Unionists will have to swallow hard to accept a Sinn Fein leader as top dog in Northern Ireland  - the state they ran in a dictatorial manner for over 50 years.

Robinson has difficulties on his right flank from renegade unionist hardliner Jim McAlister whose splinter party, Traditional Unionist Values, will definitely take significant votes.

The mainstream Ulster Unionist Party is also undergoing a revival after British Tory Party leader David Cameron worked hard to get his own party aligned with them.

Cameron will almost certainly be Prime Minister by 2011 if current polls hold up. In that scenario the Ulster Unionist Party would have far greater clout and likely more votes.

What it all means is that Sinn Fein Deputy First Minster Martin McGuinness may be sitting in the top job after the next round of elections.

That may well be too much for Robinson and his party to stomach.

Already they are demanding new rules for how power-sharing is carried out. Sinn Fein, not surprisingly, is not budging.

That is the main reason why there has been such a sour feeling in Northern Ireland in recent months as all major parties maneuver in advance of the next British general election and then the North's Assembly elections

It is why Sinn Fein is pushing very hard for the devolution of justice and security issues to the assembly as promised in the peace process.

Local control of security issues would be a major boost to Sinn Fein, That is why the DUP is  dragging its heels. Any victory for Sinn Fein will see the DUP's own popularity slide.

So there is still all to play for in Northern Ireland which is entering an exceptionally dangerous time this fall.

It remains to be seen whether the dissidents can be contained and the unionist leadership can hold its nerve. If one of those scenarios falls apart then there are troubled days ahead.