The latest Washington speculation is that the front-runner to replace Jean Kennedy Smith as United States ambassador to Ireland is the former governor of Wyoming, Michael J. Sullivan. He has confessed that he has never been to Ireland, except in his dreams.

Organised Irish-America, mainly an east coast phenomenon, does not know him. His street credibility with Irish-Americans has been questioned, mainly because he has never developed even a minor profile on Irish issues. There is even private discussion about the downgrading of the Dublin post and a lessening of President Clinton's interest in Irish affairs.

If the speculation is accurate, do we in Ireland have cause for concern? Is a key component in the peace process in danger of imminent damage? Is a prospective US ambassador unsuitable because he has no public profile in Irish issues? Is there something we should be doing about it?

Before attempting to answer these questions, some general sketching of the background might be useful. There will, of course, be difficulties for Mrs Kennedy Smith's successor. First, she will be a hard act to follow. She has done an outstanding job and done it with style and flair. Second, her successor will, in all probability, tend to be seen as a lame-duck appointment. The next president of the United States will be elected in little more than two years after the arrival of the new ambassador. Mrs Kennedy Smith's successor will be lucky to have a 2 1/2-year tenure of office, in contrast to her five-year term.

Given the limited duration of the term, it would obviously be helpful if the new ambassador knew the country and the issues in advance of the appointment. But that is not essential. The US system is good at putting new ambassadors through crash courses, and the Dublin embassy is well staffed with competent experts.

It should not be forgotten that when Mrs Kennedy Smith's appointment was announced not all the public and private comment was favourable. Elements of Irish-America, including some who are now leading her fan club, were publicly sceptical and privately annoyed. She was, they said, an unknown quantity. She had no political profile. She was not known to take any interest in Irish affairs. What was not publicly known was that she had been visiting Ireland, North and South, since the beginning of the Troubles. And in New York she had been an outstanding supporter of Irish cultural events for many years. What was predictable - but not acknowledged on her appointment - was that the Kennedy political skills would shine as brilliantly as they have done.

What now is the nature of the Dublin post? Has it been transformed by the outgoing ambassador's performance? What job description might be written for her successor?

One key point needs to be emphasised. Irish interests in our dealings with the US are asserted, represented and negotiated in the first instance by Irish politicians and diplomats. In Sean O hUiginn in Washington we have a highly experienced professional diplomat whose contribution to the crafting of the Belfast Agreement has been publicly acknowledged. The role of a US ambassador in Dublin or elsewhere relates first and foremost to the achievement of US interests.

Irish and US interests have in recent times largely coincided. This has not always been the case. One has only to recall the US attitude to Irish requests for help in the immediate aftermath of Bloody Sunday in 1972 and in the hunger-strike climate of the early 1980s to realise that Dublin and Washington have not always been on the same wavelength when it came to Northern Ireland issues.

Happily - and Mrs Kennedy Smith has contributed enormously to this - it is now possible to take it for granted that Ireland and the US share common objectives in their approach to the Northern Ireland situation. Against that background the primary task for the new ambassador is to ensure that the machinery with which to implement the underlying harmony works with maximum efficiency and effectiveness.

It is a complex piece of machinery. It has parts in Dublin, in Belfast, in London and in Washington. There are multiple centres of influence on Washington's Irish policy. There is the White House, the State Department, the Congress and organised Irish America, to name but four. An understanding of that Washington machine and an ability effectively to be a part of it is probably the most important attribute for any US ambassador. There is surely no reason to doubt the ability of a former governor when it comes to understanding and fitting into the Washington system.

I return now to the questions posed at the beginning. President Clinton has, over the last five years, shown himself to have a safe pair of hands when it comes to Ireland. His part in bringing the republican movement from violence to politics has been carefully calculated and well played. His appointment of George Mitchell to chair the Stormont talks was inspired. His appointment of Mrs Kennedy Smith to Dublin could not have been better. Why should we now doubt him as he moves to appoint a successor?

A new ambassador will bring new perspectives and a new style to the post in Dublin. We will miss Mrs Kennedy Smith, but I am sure she will be the first to urge us to give her successor the same encouragement and support that we gave her. There is no model that cannot benefit from new inputs.

Finally, it would be unwise in the extreme to seek to influence President Clinton's choice for the Dublin post. If he appoints Michael J. Sullivan he will be appointing not only a good friend and supporter but someone who shares with him membership of that most exclusive club, the governors' club. An ex-governor of Wyoming may seem an unlikely friend of Ireland. But who would have predicted five years ago that an ex-governor of Arkansas would have made such a major contribution to the achievement of peace in Ireland?

Sean Donlon is a former Irish ambassador to the United States. He is currently a non-executive director of a number of Irish companies