Canada and the U.S. have signed an agreement that paves the way for the militaries from either nation to send troops across each other's borders during an emergency, but some are questioning why the Harper government has kept silent on the deal. http://www.canada.com/ottawacitizen/news/story.html?id=47dc5095-4da9-4faa-8464-fe01289b4b7a&k=39530