Query: Barack Obama told the U.S. Coast Guard Academy "that the number one threat to the military and the world today is global warming."

Relevant passages:
Effects of global warming <=SEP=> The effects of global warming are the environmental and social changes caused ( directly or indirectly ) by human emissions of greenhouse gases . There is a scientific consensus that climate change is occurring , and that human activities are the primary driver . Many impacts of climate change have already been observed , including glacier retreat , changes in the timing of seasonal events ( e.g. , earlier flowering of plants ) , and changes in agricultural productivity .   Future effects of climate change will vary depending on climate change policies and social development . The two main policies to address climate change are reducing human greenhouse gas emissions ( climate change mitigation ) and adapting to the impacts of climate change . Geoengineering is another policy option .   Near-term climate change policies could significantly affect long-term climate change impacts . Stringent mitigation policies might be able to limit global warming ( in 2100 ) to around 2 ° C or below , relative to pre-industrial levels . Without mitigation , increased energy demand and extensive use of fossil fuels might lead to global warming of around 4 ° C. Higher magnitudes of global warming would be more difficult to adapt to , and would increase the risk of negative impacts .

Presidency of Barack Obama <=SEP=> The presidency of Barack Obama began at noon EST on January 20 , 2009 , when Barack Obama was inaugurated as President of the United States , and ended on January 20 , 2017 . Obama , a Democrat , took office as the 44th United States president following a decisive victory over Republican John McCain in the 2008 presidential election . Four years later , in the 2012 election , he defeated Mitt Romney to win re-election . He was the first African American president , the first multiracial president , the first non-white president , and the first president to have been born in Hawaii . Obama was succeeded by Republican Donald Trump , who won the 2016 presidential election .   Obama 's first-term actions addressed the global financial crisis and included a major stimulus package , a partial extension of the Bush tax cuts , legislation to reform health care , a major financial regulation reform bill , and the end of a major US military presence in Iraq . Obama also appointed Supreme Court Justices Elena Kagan and Sonia Sotomayor , the latter of whom became the first Hispanic American on the Supreme Court . Democrats controlled both houses of Congress until Republicans won a majority in the House of Representatives in the 2010 elections . Following the elections , Obama and Congressional Republicans engaged in a protracted stand-off over government spending levels and the debt ceiling .   In his second term , Obama took steps to combat climate change , signing a major international climate agreement and an executive order to limit carbon emissions . Obama also presided over the implementation of the Affordable Care Act and other legislation passed in his first term , and he negotiated rapprochements with Iran and Cuba . The number of American soldiers in Afghanistan fell dramatically during Obama 's second term , though U.S. soldiers remained in Afghanistan throughout Obama 's presidency . Republicans took control of the Senate after the 2014 elections , and Obama continued to grapple with Congressional Republicans over government spending , immigration , judicial nominations , and other issues .

Barack Obama <=SEP=> Barack Hussein Obama II ( -LSB- bəˈrɑːk_huːˈseɪn_oʊˈbɑːmə -RSB- ; born August 4 , 1961 ) is an American politician who served as the 44th President of the United States from 2009 to 2017 . He is the first African American to have served as president . He previously served in the U.S. Senate representing Illinois from 2005 to 2008 , and in the Illinois State Senate from 1997 to 2004 .   Obama was born in Honolulu , Hawaii , two years after the territory was admitted to the Union as the 50th state . Raised largely in Hawaii , Obama also spent one year of his childhood in Washington State and four years in Indonesia . After graduating from Columbia University in 1983 , he worked as a community organizer in Chicago . In 1988 Obama enrolled in Harvard Law School , where he was the first black president of the Harvard Law Review . After graduation , he became a civil rights attorney and professor , teaching constitutional law at the University of Chicago Law School from 1992 to 2004 . Obama represented the 13th District for three terms in the Illinois Senate from 1997 to 2004 , when he ran for the U.S. Senate . Obama received national attention in 2004 , with his unexpected March primary win , his well-received July Democratic National Convention keynote address , and his landslide November election to the Senate . In 2008 , Obama was nominated for president , a year after his campaign began , and after a close primary campaign against Hillary Clinton . He was elected over Republican John McCain , and was inaugurated on January 20 , 2009 . Nine months later , Obama was named the 2009 Nobel Peace Prize laureate .   During his first two years in office , Obama signed many landmark bills . Main reforms were the Patient Protection and Affordable Care Act ( often referred to as `` Obamacare '' ) , the Dodd -- Frank Wall Street Reform and Consumer Protection Act , and the Do n't Ask , Do n'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 stimulus amidst the Great Recession , but the GOP regained control of the House of Representatives in 2011 . After a lengthy debate over the national debt limit , Obama signed the Budget Control and the American Taxpayer Relief Acts . In foreign policy , Obama increased U.S. troop levels in Afghanistan , reduced nuclear weapons with the U.S.-Russian New START treaty , and ended military involvement in the Iraq War . He ordered military involvement in Libya in opposition to Muammar Gaddafi , and the military operation that resulted in the death of Osama bin Laden .   After winning re-election by defeating Republican nominee Mitt Romney , Obama was sworn in for a second term in 2013 . During his second term , Obama promoted greater inclusiveness for LGBT Americans , with his administration filing briefs that urged the Supreme Court to strike down same-sex marriage bans as unconstitutional ( United States v. Windsor and Obergefell v. Hodges ) . Obama also advocated gun control in response to the Sandy Hook Elementary School shooting , and issued wide-ranging executive actions concerning climate change and immigration . In foreign policy , Obama ordered military intervention in Iraq in response to gains made by ISIL after the 2011 withdrawal from Iraq , continued the process of ending U.S. combat operations in Afghanistan , promoted discussions that led to the 2015 Paris Agreement on global climate change , initiated the sanctions against Russia following the invasion in Ukraine , brokered a nuclear deal with Iran , and normalized U.S. relations with Cuba .   Obama left office in January 2017 with a 60 % approval rating . He currently resides in Washington , D.C. His presidential library will be built in Chicago .