Why has NATO continued to expand into Eastern Europe and the former Soviet Union?

What role might NATO play in today's world?

It certainly is a debatable proposition that the NATO alliance may have already outlived it's utility . That is the position people like Rep. Ron Paul has taken . He argues that an expanding NATO is a cover for US interventionism .

I do not buy that part of his argument but NATO does seem to be an alliance without a well defined mission (although Vlad Putin may have changed that dynamic this week with his bluster ). NATO has been a key ally in Afghanistan so it appears that it is willing to expand it's responsibilities beyond containment of Russia. We in turn came to the service of the NATO nations when we helped intervene in the Balkans. I think that was a good mission to undertake.

Call it NATO or some other cross Atlantic alliance ,I think continued cooperation of free nations is essential in the world we live in . The former Soviet satellite nations that are being added to the NATO umbrella are some of the most dynamic new democratic free nations on the planet. As a matter of fact;I think "old Europe " would do well to see what is happening there and remember where they once were . A united Europe that did not incorporate these nations would be incomplete.

Nearly fifty-three years after its creation, NATO remains the core of the United States commitment to Europe and the bedrock of our security and stability in a still dangerous world. Secretary Powell made this point best in his confirmation hearings when he observed that "the value of NATO can be seen by the fact that ten years after the Cold War, nations are still seeking to join the Alliance, not to leave it." NATO can meet new threats, building cooperation with former enemies, and ensuring stability in Southeast Europe, giving time for this region to become a part of the European mainstream. NATO's fundamentals -- its shared values, and common commitment to defend freedom -- remain sound. [Marc Grossman, Under Secretary for Political Affairs Testimony Before the Senate Armed Services Committee Washington, DC February 28, 2002]

I think they deserve our continued defense guarantees .

I, too, agree with the continued alliance with freedom loving countries around the globe. Without these crucile contacts, us helping them and them helping us, we would likely be in a more perilous position. NATO's purpose is still intact. The role and mission must remain adaptable and assertive.