The unholy trinity in open economy macroeconomics is pretty simple. It's impossible for a country to do the following three things at the same time:
1) Maintain a fixed exchange rate
2) Maintain an open capital market
3) Run an independent monetary policy
One of the issues with macroeconomic policy coordination right now is that different countries have chosen different options to sacrifice. China, for example, has never opened its capital account. The United States, in pursuing quantitative easing, has basically chucked fixed exchange rates under the bus, no matter how many times Tim Geithner utters the "strong dollar" mantra
in his sleep to reporters.
These policies are generating a fair amount of blowback from the rest of the world, forcing President Barack Obama to defend the Fed's actions. And it appears that the developing countries are mostly following China's path towards regulating their capital account to prevent exchange rate appreciation and the inward rush of hot money.
How does this end? I think it's gonna end with a lot more capital controls for a few reasons:
1) It's the political path of least resistance;
2) Capital controls are seen as strengthening the state;
3) The high-growth areas of the world don't need a lot of capital inflows to fuel their continued growth.
What intrigues me is how the financial sector responds to a situation in which their freedom of action in emerging markets becomes more and more constrained. It's possible that they could pressure the Fed to change its position in the future. It's also possible, however, that big firms could see these controls as a useful barrier to entry for new firms.
My money is on the former response, however.