What competition policy in Europe?

Two completely contradictory claims are sometimes made: In the United States, the competition authorities have let corporate concentration and companies with dominant positions reappear, and this is very bad for the US economy (stifling innovation, slowing productivity); In Europe, the competition authorities must encourage the emergence of large “European champions” capable of rivalling their US or Chinese competitors and therefore inevitably having dominant position s in the European market. How can the contradiction between these two claims be reconciled? Probably by looking at returns to scale: In a “normal" sector with decreasing returns to scale, size does not improve efficiency ; i t simply leads to oligopoly rents. The authorities must therefore combat concentration and break up monopolies; large foreign companies do not pose a threat because they are inefficient; In a “new” sector with increasing returns to scale, there is a natural monopoly: a large European company must be allowed to form, otherwise large foreign companies will dominate the European market. But the authorities must regulate this company to limit its monopoly rents and check that it is investing sufficiently. The competition authorities therefore have the complex task of determining in each sector whether returns to scale are increasing or decreasing.