It is six years this week since the Czech Republic, Hungary and Poland joined NATO - a milestone in the history of both the alliance and Central Europe. Last year NATO was enlarged even further, to include Slovakia, Slovenia, Bulgaria, Romania and the three Baltic states. We look at Central Europe's relationship with the Alliance.
Few would have imagined in 1989 that within 15 years most of the former Warsaw Pact armies would be flying the NATO flag. But the Alliance now stretches across most of Eastern Europe, from the Baltics to the Black Sea. The US President George W Bush was keen to stress the significance of this transition, during his recent trip to Slovakia.
"Last year the former member of the Warsaw Pact became a member of NATO, and took its rightful place in the European Union. Every Slovak can be proud of these achievements, and the American people are proud to call you allies, and friends, and brothers in the cause of freedom."
Slovak analyst Ivo Samson says the link between membership of NATO and the EU is not an accidental one: the EU, he says, only decided to move eastwards after the success of NATO's initial expansion. Mr Samson says for this the region's leaders should be grateful.
"Prime Minister Dzurinda should thank first of all the American president for the initiative of the United States for the push to enlarge NATO. Because it was the enlargement of NATO which brought the European leaders to the idea to enlarge the EU. So there are reasons enough simply to be really grateful to the United States."
The former Warsaw Pact members are slowly transforming huge and outdated armies into modern smaller forces, specialising in certain areas of expertise. But the transition hasn't always been easy. The Czech Republic, for example, had a baptism of fire. Less than two weeks after joining the Alliance in March 1999, the country found itself going to war against Yugoslavia - a traditional ally. Karel Kovanda is the outgoing Czech ambassador to NATO.
"The Kosovo campaign started twelve days after we became members of the alliance and I think the manner in which NATO makes its decisions took our politicians in Prague somewhat by surprise. And so, in the first days of the Kosovo campaign, our leadership found itself in two difficulties. One was the one unfamiliarity with the decision-making process and the other difficulty was public opinion, which was reflected in the view of some of our politicians. Public opinion, for a variety of reasons, was staunchly against the bombing and in favour of Belgrade even if it was the Belgrade of a Milosevic."
Despite such tests of faith, NATO membership remains generally popular among the people of the new members, who remember decades of Soviet occupation. For many people in the West NATO membership is an abstract, even irrelevant concept: for many Czechs, Slovaks and other former citizens of the eastern bloc, however, it's a real guarantee of security.
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