President Donald Trump’s continuing courtship of Russian leader Vladimir Putin is casting darkness over U.S. foreign policy. But there is a ray of light where Russia is concerned. The Pentagon is now reportedly beginning preliminary research on a ground-launched cruise missile that would be prohibited under the terms of the Intermediate-range Nuclear Forces Treaty. This is an overdue step toward making Russia pay for its violations of that accord, and perhaps even positioning America for strategic advantage in a post-INF world.