No American leader would tolerate Canada or Mexico joining a military alliance headed by another great power

By Prof. John J. Mearsheimer • University of Chicago  Feb. 8, 2015http://www.nytimes.com/2015/02/09/opinion/dont-arm-ukraine.html The Ukraine crisis is almost a year old and Russia is winning. The separatists in eastern Ukraine are gaining ground and Russia’s president, Vladimir V. Putin, shows no signs of backing down in the face of Western economic sanctions.Unsurprisingly, a growing chorus of voices in the United States is calling for arming Ukraine.