To begin with, the law of comparative advantages does not mean that each country does equally well. It simply means that given the limits of geography and education, each nation will do as well as it can. And it is at this point that Ricardo's theory both drives much of contemporary trade policy and poses the core problem for the European Union. The theory is not, in my opinion, wrong. It is, however, incomplete in looking at the nation (or corporation) as an integrated being and not entities made up of distinct and diverse interests. There are in my mind three problems that emerge from the underlying truth of this theory.
The first of these is the problem of geopolitical consequences. Economic power is not the only type of power there is. Disparate rates of economic growth make the faster growing economy more powerful in its relation to the slower growing economy. That power is both political and military and can be used, along with economic advantage, to force nations into not only subordinate positions but also positions where their lesser comparative advantage diminishes even further. This does not have to be intentional. Maximizing comparative advantage makes some powers stronger than others, and over time that strength can leave the lesser power crippled in ways that have little to do with economics.