Seven former Soviet bloc countries are expected to get formal invitations to join NATO during this week's Prague summit. U.S. President George W. Bush has backed the expansion as a way to unite Europe and keep new democracies on the path to reform.
NATO began in 1949 as an alliance of countries with a common goal: blocking Soviet expansion.
But with the end of the Cold War, the alliance and its mission changed. Former enemies became allies. In 1999, Hungary, Poland, and the Czech Republic became the first former Soviet bloc countries to join NATO. In Prague, the expansion eastward will continue.
Lithuania, Estonia, Latvia, Romania, Bulgaria, Slovenia and Slovakia are the current candidates for membership.
White House National Security Advisor Condoleezza Rice says it all would have been unthinkable not that long ago. "This is a summit," she observed, "that is going to celebrate an historic moment for NATO, which is the expansion of NATO into territories that I think nobody ever thought NATO would expand into."
President Bush is expected to applaud the NATO expansion process in a speech Wednesday in Prague. Before returning to Washington Saturday, he will visit two of the countries expected to get invitations to join the alliance: Lithuania and Romania.
Some observers refer to the stops in Vilnius and Bucharest as part of a presidential "victory lap," a chance for Mr. Bush to celebrate another big step in his vision of a Europe that is "whole, free and at peace."
But some foreign policy experts say they are concerned that the expansion of NATO is happening far too quickly and new members are being admitted who are not ready to bear the responsibilities of membership.
"One of the problems I have with the enlargement debate is how we have not, in fact, have not had debate for the past year plus," said Ivo Daalder, a foreign policy analyst with the Brookings Institution in Washington. "Here we are taking seven countries into the alliance, the ostensible purpose being to complete and extend the European zone of peace, and quite frankly we are getting people into this alliance who do not belong in this alliance yet."
He notes that Slovakia has only had one free election, and Romania and Bulgaria, while making progress in recent years, are far behind countries like Hungary and the Czech Republic.
Congress has held a number of hearings on that very issue.
Senator Gordon Smith, Chairman of the Senate Subcommittee on Europe, says alliance membership will give these countries a boost on the path of reform. "I think there is a recognition in the U.S. Senate that while NATO is an evolving alliance, it remains a military alliance," he said. "But even more it is one of the best levers the American people have through their government to influence peaceful change in Eastern Europe and these countries newly liberated from totalitarianism."
Last month, NATO Secretary-General George Robertson delivered a speech in Washington on the future of the alliance. He said he believes enlargement will strengthen the alliance and bring an end to "artificial divisions in the Old World."