I wrote yesterday of the UK's opposition to global tax cooperation, especially when it comes to developing countries. Yet look at this by Larry Summers in the FT from May:

First, the US should take the lead in promoting global co-operation in the international tax arena. There has been a race to the bottom in the taxation of corporate income as nations lower their rates to entice business to issue more debt and invest in their jurisdictions. Closely related is the problem of tax havens that seek to lure wealthy citizens with promises that they can avoid paying taxes altogether on large parts of their fortunes. It might be inevitable that globalisation leads to some increases in inequality; it is not necessary that it also compromise the possibility of progressive taxation.

Second, an increased focus of international economic diplomacy should be to prevent harmful regulatory competition. In many areas it is appropriate that regulations differ between countries in response to local circumstances. But there is a reason why progressives in the early part of the 20th century sought to have the federal government take over many kinds of regulatory responsibility. They were concerned that competition for business across states, and their ease of being able to move, would lead to a race to the bottom.

Harvard knows this.

Why doesn't Whitehall?