Feud between SpaceX and ULA over space contract grows more intense, Washington Post
"This week, Russian Deputy Prime Minister Dmitry Rogozin said he would prohibit the export of Russian-made engines used in many U.S. rocket launches. That could eventually cause a disruption in how the Pentagon sends military satellites into orbit. And it plays into the hands of Musk, who is arguing that the nation's security interests in space shouldn't be dependent on the Russians."
"As we move forward, it is important that we fully understand our nation's independent capabilities with regard to ISS operations," the letter states. "While this new development is not related to access to the ISS for our astronauts in the next few years, it certainly pertains to the strength of our partnership with Russia. If Mr. Rogozin's statement proves to be accurate, we will have to take a step back and evaluate the costs and benefits of maintaining ISS beyond 2020 without our Russian partners."