The 15 EU member states, faced with the choice, did not turn their backs on candidate countries at the Nice summit this month, the Minister for Foreign Affairs has said.
"The task of making compromises may not always provide the most elegant solution, but it does reflect the reality of today's Europe," Mr Cowen said.
"The cause for encouragement is surely that despite the conflicting pressures on 15 national governments, it was possible to reach agreement, which will allow the historic process of enlargement to proceed."
Mr Cowen, who was at the Nice summit with the Taoiseach, was addressing the Institute of European Affairs in Dublin yesterday on the state of the European Union.
He said the member state governments at Nice had recognised their obligation to protect vital national interests but also to contribute to reaching a solution that responded to the importance of the issues at stake.
He said there was "a widespread recognition of where Europe's interests, with which our national interests are inextricably linked, lay. I believe this explains why there was sufficient give-and-take to allow agreement, eventually, to be reached."
Mr Cowen said the summit outcome must be seen as a package, with movement in one area balanced by changes in others. He outlined major decisions taken, including reforms of the European Commission and qualified majority voting.