"The Future of Capitalism," Paul Collier, Harper, 256 pages, $29.99.

Paul Collier’s new book revisits the familiar territory of tales of the West’s decline. But it stands out because it is pragmatic, blunt — and optimistic.

In “The Bottom Billion,” published in 2007, Collier examined the plight of the world’s poorest. Now he turns to rich countries, which he believes are morally bankrupt and ruled by predatory elites.

The patriotic legacy of World War II, he said, allowed Western countries to combine the strengths of the market with a protective web of reciprocal obligations.

By the 1980s, two toxic ideologies were ascendant. One was modern economics, which, Collier said, assumes individuals are selfish and rootless, and argues for a freewheeling kind of globalization because it is efficient.

The other, he said, urges people to claim a proliferating set of rights and promotes “new victim groups seeking privileged treatment.”

Collier, a professor at Oxford University, grew up in a working-class British steel town. In some circumstances, he said, society has a duty of rescue — to refugees, for example, or teenagers trapped in dead-end jobs. But in most domains the governing principle should be “reciprocity.”

For example, firms should be loyal to their staffs. At the national level, rich cities should share more of the spoils with laggard cities; migration must be calibrated to benefit the host population.

Some of these ideas work better than others. A chapter on families, for example, ends limply with the suggestion that the oldest generation should try to police the obligations of the extended clan. Collier is more convincing on larger public policies.