After winning re-election by defeating Republican opponent Mitt Romney, Obama was sworn in for a second term in 2013. During this term, he promoted inclusion for LGBT Americans. His administration filed briefs that urged the Supreme Court to strike down same-sex marriage bans as unconstitutional ("United States v. Windsor" and "Obergefell v. Hodges"); same-sex marriage was legalized nationwide in 2015 after the Court ruled so in "Obergefell". He advocated for gun control in response to the Sandy Hook Elementary School shooting, indicating support for a ban on assault weapons, and issued wide-ranging executive actions concerning global warming and immigration. In foreign policy, he ordered military interventions in Iraq and Syria in response to gains made by ISIL after the 2011 withdrawal from Iraq, promoted discussions that led to the 2015 Paris Agreement on global climate change, oversaw and ultimately apologized for the deadly Kunduz hospital airstrike, continued the process of ending U.S. combat operations in Afghanistan in 2016, initiated sanctions against Russia following the invasion in Ukraine and again after interference in the 2016 U.S. elections, brokered the Joint Comprehensive Plan of Action nuclear deal with Iran, and normalized U.S. relations with Cuba. Obama nominated three justices to the Supreme Court: Sonia Sotomayor and Elena Kagan were confirmed as justices, while Merrick Garland faced partisan obstruction from the Republican-majority Senate led by Mitch McConnell, which never held hearings or a vote on the nomination. Obama left office in January 2017 and continues to reside in Washington, D.C.