European Defence: "why?", past, present and future,

So it seems that as budgets get presented again, it is time for the USA to once more tell Europe that it needs to honour its defence commitments under NATO. Everyone will complain that they can't and leave it to the USA to pay. Given their own financial dire straits, one is left to wonder for how much longer we'll be able to do this... Why should we have a EU army? Because size matters Now if anyone's reading and if this isn't the first post you're going through, you've probably figured out that I'm pretty pro-European integration. So, it won't surprise anyone that I'm in favour of a single European Army. There are 3 main reasons for this: First, in the unlikely scenario that anyone would wake up one day and think it was a good day to invade Europe, what would make you think twice (if nuclear deterrence wasn't enough)? To fight the Baltics, then Finland, Sweden, etc making then fall like dominoes, or to fight a cohesive army drafted by the 500 million citizens of the 27 nations of the EU (to paraphrase "300")? Secondly, it would probably be cheaper to run one big army than 27 small ones. There are issues of interoperability and wasteful duplication of efforts. There are also issues of natural monopolies, where an enormous purchaser is necessary in order to take up the costs of purchasing enormously expensive research (sometimes cheer size matters more than relative values. In this case, 4% of a single US budget accomplishes more than the sum of four percent contributions by all 27 EU member states. From a purely economic analysis perspective integration represents an improvement in returns to scale, meaning that the same inputs should produce more output. Finally, the purchase of this enormously expensive research is crucial for development, as there are huge potential spillovers from military to civilian R&D. The telephone, canned food, the internet, GPS, are only a few examples of such spillovers. Given that private investment is what pushes growth most consistently, defence research by association must also be rather important for that purpose. The unsuccessful past It is interesting to notice that European military ntegrationi did not take place for, at least 5 reasons: 1) the difference between the original preferred proposal and the one to be ratified by the states, 2) French sovereignty fears, 3) the death of Joseph Stalin, 4) the ability of European countries to piggy back on the USA via NATO, and 5) the shift in geo-political concerns brought about by the Korean War. The Present Obviously, over time as the military rebuilt themselves they became more rooted and as the fear if invasion disappeared, so did the need for enhanced and pooled protection. Moreover this national identity is supported by national quasi and total monopolies in the defence industry, who are shielded from competition by the special status that their sector has under national law. The slow future Nonetheless, there's no point in sobbing. The truth is that, in the absence of a war (at which point it would be too late) or the USA cutting back their military presence due to economic decadence (which is not impossible), European military integration will be an excruciatingly slow process. To that end however this might just be the most informed set of opinions and advices available on the topic. Until any relevant shock happens this is still only what we should do, not what we need to do.