Over the years I have had occasion to argue the merits of the EU - and of its single currency - with Conservative British Eurosceptics. But this week, I have been arguing the merits of the European Reaction Force with three US Senators who are strong supporters of NATO, and who fear this new project will weaken the Alliance.
Why have our extreme left and "republicans" joined with these American NATO advocates in opposition to the European Rapid Reaction Force (ERRF)?
American opposition to the ERRF derives from a fear that the initiative will weaken NATO, whereas the Irish opponents see this new development as a NATO plan to strengthen that organisation. Clearly, they can't both be right.
The Americans who are concerned about the ERRF believe that its emergence might strengthen the hands of isolationists in the US who argue for American disengagement from Europe. They fear that these isolationists will be tempted by the emergence of this new force to argue that Europe can look after itself and will no longer need US assistance through NATO to deal with crises in our region.
While this argument could have some validity, I feel that our Europe simply cannot afford, as the treaty opponents apparently wish, to remain totally dependent on NATO, and thus on the US, for effective peace-making in Europe.
This is surely one of the lessons of Bosnia, for during that conflict Europe was miserably shamed when the forces of European states proved unable to relieve a besieged Bosnian city simply because they lacked the capacity to do so without a US helicopter lift - and the Americans were unwilling to risk the lives of their helicopter pilots in such an operation.
That episode made it clear that Europeans like ourselves who are concerned about human rights need another force, in parallel with but separate from NATO, that can be called upon to save European lives when they are put at risk.
Our far left and "republicans" have now been joined in their opposition to our EU involvement by right-wing religious elements preoccupied with a belief that the EU will impose godless values on our society.
What seems to be common to this odd mixum-gatherum of Nice Treaty opponents - much the same crew as opposed the previous four EU treaties - is a "drawbridge mentality" that sees involvement with the world outside Ireland almost entirely negatively.
Ireland, they appear to feel, must preserve its purity by staying away from any engagement with the big bad world. But, although these anti-Europeans see us as much purer than all our neighbours (no nasty defensive alliances, for example), at the same time they seem to believe that Ireland has nothing to offer Europe. They show no sign of recognising that our values are worth promoting among our partners and that, together with other like-minded peoples in the EU, of whom there are many, we might succeed in making Europe a better, and safer, place for all.
There is certainly no sense that they accept that, with all its faults and weaknesses, Europe has values that are needed in the world. Thus these anti-Europeans want to ignore the fact that the EU has created a unique zone of peace, now stretching from Ireland to Bulgaria and from Portugal to Finland - even if not yet to the Western Balkans.
Europe - not just the EU but Europe as a whole - has also created a zone within which there is supra-national protection for human rights, and where capital punishment is now inconceivable. Europe, and above all the EU, has led the world in its generosity in providing aid to the developing world.
And it is Europe, led by the EU, that has created a worldwide movement to protect our global environment.
None of these advances is without flaws - flaws that we in Ireland could be doing much more to eliminate. But none of these remarkable developments, reversing the bitter tide of history on so many fronts, would ever have come into existence without Europe.
Instead of turning aside from Europe, as we are being urged to do by those who want us to reject the Nice Treaty, and thus block the enlargement of the Union, can we not instead set about playing a positive and constructive part in building on the remarkable foundations laid by so many generous-minded European visionaries of the second half of the last century? That is what this referendum is really about.
Let me, in conclusion, nail three untruths being remorselessly propounded by unscrupulous opponents of the Nice Treaty:
1. Contrary to persistent claims by opponents of the treaty, it is, in fact, about enlargement of the community. That is its stated purpose as set out in the preamble, and anyone who listens to the radio can daily hear the neutral Referendum Commission stating unequivocally that this treaty "contains what EU governments consider necessary for enlargement".
2. It is absolutely false that the Amsterdam Treaty already makes provision for five new states to join without any further treaty. The Amsterdam Treaty contained nothing whatever to modify the existing treaties so as to enable any new state to participate in the Council of Ministers, Parliament, Commission or other institutions. Such participation consequently requires the amendments contained in the Nice Treaty, without which no applicant can become a member of the EU.
3. It is simply false to allege that this treaty is concerned with "the militarisation of the EU", as claimed by Andy Storey on this page last Wednesday. The only references to military matters in the Nice Treaty relate to the Rapid Reaction Force that is being created for peacekeeping purposes - participation in whose operations is, of course, on a purely voluntary basis, to be decided in each instance by our democratic parliament.
What this treaty also does is specifically reiterate the earlier Amsterdam Treaty provision that protects our military neutrality and that of three other neutral member-states, by stating unequivocally that the policy of the EU "shall not prejudice the specific character of the security and defence policy of certain member-states".
The fact that opponents of the treaty have felt it necessary to misrepresent its provisions in these three significant ways deprives them of any credibility. Accordingly, their flawed case deserves to be rejected by the electorate next Thursday.