The military could ease its manpower shortage by letting foreigners join up. It is hard to pick up a newspaper these days without reading about Army and Marine Corps recruiting and retention woes. Nonstop deployments and the danger faced by troops in Iraq are making it hard for both services to fill their ranks. The same goes for the National Guard and Reserves. (The Navy and Air Force, which are much less in harm's way, have no such difficulty.) Just to stay at their present sizes, the Army and Marines are shoveling money into more advertising, extra recruiters and bigger...