The USA remains the world's leading economic and military power. Its Gross Domestic Product of over $18 trillion and constitutes 24% of world GDP.
The US is the leading power in the G20/G8 group of nations and has strong ties with Israel, which is its traditional ally in the Middle East.
The President of the USA, as Commander-in-Chief of the country's armed forces, is perhaps the world's most powerful man. The USA has the most experienced, skilled and best armed military, as well as sophisticated nuclear missiles, including the potential for defence in space.
The USA is the leading power in the North Atlantic Treaty Organisation (NATO) and is a permanent member of the United Nations Security Council. New York hosts the headquarters of the United Nations Organisation.
The USA faces many problems in the 21st century. China is expanding its military and is contesting the South China Sea.; Russia has re-emerged on the world stage and continues to test the US and the other members of NATO. Cyberwarfare is a threat and the USA has been indecisive over the Syrian conflict and the terrorist group with calls itself Islamic State.
President Obama was, arguably, one of the most aggressive Presidents of recent times. He helped overthrow Colonel Gaddafi in Libya and continues to order many drone attacks in Pakistan. He also authorised a threefold increase in the number of American troops in Afghanistan. In 2011 President Obama ordered and oversaw the Navy SEAL raid that killed Osama bin Laden.