Is the Euro Necessary for a Peaceful Europe?

One of the arguments you hear for the German willingness to extend itself to bail out Greece, Italy, Spain, Portugal, and Ireland is that the Eurozone is not just a monetary union for the sake of financial advantage. The integration of Europe serves a much more important function, peace. By having Europeans see themselves as Europeans, something that arises from tighter and integrated relations, it makes the likelihood of war in Europe less likely. By considering their way of life to be enmeshed with each other, they see other European nations as variations on us instead of as an alien them that could be dehumanized, a major step towards war.

After the European wars of the 19th and especially 20th century, there is good reason to do whatever one can to make entire continents more likely to live together peaceably. But is there really a rational fear there? Is Europe now a different place? Is the threat of a war between major European powers something that is still in the realm of possibility? Is Europe more mature? Has globalization and the complete reinvention of the world economy made European continental war a concern of the past, or could old antagonisms arise again?