Obama signed many landmark bills into law during his first two years in office. The main reforms include: the Affordable Care Act (ACA or "Obamacare"), although without a public health insurance option; the Dodd–Frank Wall Street Reform and Consumer Protection Act; and the Don't Ask, Don't Tell Repeal Act of 2010. The American Recovery and Reinvestment Act of 2009 and Tax Relief, Unemployment Insurance Reauthorization, and Job Creation Act of 2010 served as economic stimuli amidst the Great Recession. After a lengthy debate over the national debt limit, he signed the Budget Control and the American Taxpayer Relief Acts. In foreign policy, he increased U.S. troop levels in Afghanistan, reduced nuclear weapons with the United States–Russia New START treaty, and ended military involvement in the Iraq War. He ordered military involvement in Libya for the implementation of the UN Security Council Resolution 1973, contributing to the overthrow of Muammar Gaddafi. He also ordered the military operation that resulted in the killing of Osama bin Laden.