The second question at the end of Ahamed's introductory essay asks if we are at a point similar to the 1930s when an absence of global economic leadership made the Great Depression much worse:

Charles Kindleberger ... attributed the 1929 collapse to a failure of global economic leadership. In his view a well functioning world economy required some country to act as the leader, in effect to do more than its fair share ... recognizing that smaller countries will freeload off its efforts... But the leaders of the U.S. were too parochial and insular to seize the opportunity. ...

Has the US been so weakened by its accumulated current account deficits, its banking debacle and its foreign policy disasters that it is incapable of bearing more than its fair share of the burden?

As I noted here, I think we are in a situation where we were more than big enough to break the U,S. and world economies, but are not big enough to fix the problem on our own - particularly after absorbing the costs of financial collapse onto our domestic balance sheets. However, while crisis has made it clear that we cannot fix the world economy by ourselves, I don't think the crisis is the fundamental reason for this, the distribution of world economic growth in recent decades would have led to this outcome with or without the crisis.

Though we can't fix the problems by ourselves, we are still big enough to have a large influence on the global economy, and we need to do our share, but that influence will become more diluted with time. Unlike in the past when we could expect a single country to emerge and fulfill the role of providing global economic insurance, the world will continue to grow, and that growth will be balanced enough to ensure that no country will have a large enough share of world output to serve as the "supplier of capital of last resort" for the global economy. 

If that's the case, then we must cooperate internationally and develop institutions that are capable of producing a shared and common response to economic difficulties. With no country big enough to save the world on its own, no individual country will be willing to take strong action in a downturn without assurances that their neighbors will also act. This is because money spent domestically in an attempt to stimulate the economy can leak across borders, and to solve this countries will either impose protectionist measures to ensure the spending remains with their borders, or they will not respond with full force, if they respond at all. 

This is not an imagined problem, we've seen the difficulties in coordinating monetary and fiscal policy across countries in response to the present crisis, we've seen moves toward protectionism, and I hope we can find a way to improve and do collectively what Kindleberger would have had the global leader do. That will require, for one, that the US realize that it must be part of a team rather than the person in charge giving all the orders, and giving the rest of the world the respect it deserves in formulating these decisions. There have been some encouraging signs, notably the decision at the recent G20 meetings to enhance the resources available to the IMF, the meetings themselves seemed to move toward a more cooperative governing structure, something that certainly wasn't hurt by having a new US administration, and some common views on global financial regulation emerged. But at the same time there was little cooperation on fiscal policy measures, and many of the initiatives were more show than substance. So we shall see.