So far, few politicians have embraced my plan for a Marshall Plan Tax. The idea is that every time a think-tanker, op-ed writer or retired senator calls for a new Marshall Plan or a moonshot-type initiative to solve a social problem, they would have to pay a tax of $50. Within a few months, we’d have enough money to pay for an actual new Marshall Plan.

The problem with my proposal is this: Do Marshall Plans work? If this country really did galvanize its best minds and billions of dollars to alleviate poverty somewhere or to solve some complicated problem, could we actually do it?

Well, the U.S. has been engaged in a new Marshall Plan for most of the past decade. Between 2002 and 2010, the U.S. spent roughly $19 billion to promote development in Afghanistan. Many other nations have also sent thousands of aid workers and billions of dollars.

In some spheres the results have been impressive. Nearly two-thirds of Afghans now have access to basic health services, up from 9 percent a decade ago. Under the Taliban, 900,000 boys and no girls attended schools. Now more than seven million Afghans attend school, and 35 percent of them are girls, according to the United States Agency for International Development.