The son of a Kenyan father and US mother, who divorced when he was a child, Obama was raised in Hawaii and Indonesia. He graduated in political science from Columbia University in 1983. A community organizer in Chicago from 1985 to 1988, he became active in the Democratic Party after graduating from Harvard Law School in 1991. He was elected to the Illinois Senate (1996) and then the US Senate (2004). In the 2008 presidential race he won a hard-fought primary campaign against Hillary Clinton, and then defeated the Republican John McCain to become the USA’s first Black president. Obama’s campaign was characterized by inspiring oratory that raised great—perhaps unrealistic—hopes for his administration. In office Obama was hampered by fiercely partisan Republican opposition in Congress. His significant domestic achievement was the Patient Protection and Affordable Care Act (2010), which provided for health insurance for all US citizens; but this has proved a controversial change, viewed by opponents as unwarranted government interference. In foreign affairs he ended the US military presence in Iraq (2011). In 2012 Obama defeated Mitt Romney to win re-election. During his second term, his ability to implement major domestic reforms was limited by the Republican control of Congress, but internationally he was able to reach a nuclear agreement with Iran and ratified the Paris climate agreement. He was succeeded by the Republican Donald Trump, who immediately set out to undo the achievements of the Obama presidency. He was awarded the Nobel Peace Prize in 2009.