Does the EU guarantee peace like it guarantees bank deposits I wonder...
Methinks the 'peace guarantee' has been much overused and that all that's happened is that national and international tensions have been simmering away as usual. It's really that not hard to maintain peace within modern Europe when economic times appear 'good' and the EU is seen as doling out money from richer nations to poorer ones at no apparent cost to the donors. The problem comes when the massive cost becomes apparent, the money stops flowing and resentment then starts building on both sides. I don't think it's a major leap of imagination to consider that what's been done in the EU could have sown the seeds of a major crisis which could spiral out of control into conflict, not necessarily WWIII however. Whether those seeds germinate will be determined by whether or not we manage to get ourselves out of this financial mess and whether or not large swathes of disaffected people around Europe start turning to extremists for a 'solution' to their woes and forming dangerous political allegiances based on historical resentments. I seem to recall a certain German leader taking advantage, very cleverly and systematically, of simmering resentment and turning it into the worst possible form of extreme nationalism. We'd all like to hope nothing like that could happen again but IMHO there are the conditions brewing for dangerous and very long lasting tensions in Europe.
It strikes me that if the inherent tensions between nations are such that war could conceivably start, it'll take a lot more than a bunch of self important Eurocrats to stop that.