students. He supports the increased availability of charter schools. Environment Walker signed a "No Climate Tax" pledge promising not to support any legislation that would raise taxes to combat climate change and has been a keynote speaker at the Heartland Institute, which promotes climate change denial. He proposed funding cuts for clean energy and other environmental programs. He has proposed giving many powers of the Environmental Protection Agency to the states. He opposed the Obama administration's efforts to reduce carbon emissions. Foreign policy In 2015, Walker indicated that he favored providing arms to Ukraine to fight in the Russo-Ukrainian War. In 2015, Walker stated in an interview with Charlie Sykes that if elected president, he would "absolutely" decide on his first day in office to "cancel any Iranian deal the Obama administration makes," even if European allies which were also party to an agreement opted not to reimpose sanctions. In 2015, while campaigning for the Republican presidential nomination, Walker faulted Obama for lack of strategy in dealing with the Islamic State of Iraq and the Levant group, and did not rule out sending U.S. troops to Syria to engage in ground combat with ISIL there. In February 2015, when asked about the war in Syria, Walker said that the U.S. should "go beyond just aggressive air strikes. We have to look at other surgical methods. And ultimately, we have to be prepared to put boots on the ground if that's what it takes." In a 2015 interview, Walker said that "the most significant foreign policy decision" of his lifetime was President Ronald Reagan's firing 11,000 striking air traffic controllers in 1981, saying: "It sent a message not only across America, it sent a message around the world ... [that] we weren't to be messed with." In 2015, Walker opposed rapprochement in relations between the U.S. and Cuba. Guns Walker has supported gun rights. In July 2011, he signed a bill into law making Wisconsin the 49th concealed carry state in the United States, and on December 7 of that same year he signed the castle doctrine into law. In January and April 2015 speeches in Iowa, Walker included passing those laws among his accomplishments. The National Rifle Association gave Walker a 100% ranking in 2014. On June 24, 2015, Walker signed two bills into law, one which removed the state's 48-hour waiting period for buying a gun and another which