Anders, thanks for your comment and question. I think the key reason that the FED and other central banks nowadays don't look a lot at M2 as a determinant for inflation is that they consider capacity utilization (the demand and supply balance on the markets for goods and services) as the key driver of inflation. Thus, they would not care too much about M2 even in a closed economy. But it is true that openness via trade has in recent decades allowed for a lot of negative pressure on prices to spread around the world. I would be worried, though, about the impact of soaring M2 on asset prices. In this sense I would agree with you that there is a risk that the "excess money simply does not leave fast enough." Opening up the capital account to outflows may release some of this pressure. However, this could run into other complications, and, at the end of the day, the only way to contain the risks associated with rapidly rising M2 is to reduce the pace of expansion.