It has often been said that American Presidents have much greater power in foreign affairs, than in domestic affairs, since they have to work with Congress to accomplish domestic goals.
But in actuality, Presidents are subject to the actions of other nations and their leaders, and are often taken aback by stunning, surprising events that transform the course of history.
Examples from Franklin D. Roosevelt to Barack Obama abound:
FDR and the Japanese attack on Pearl Harbor, Hawaii in 1941
Harry Truman and the outbreak of the Korean War in 1950
Dwight D. Eisenhower and the U-2 Spy Plane Incident 1960
John F. Kennedy and the Berlin Wall 1961
John F. Kennedy and the Cuban Missile Crisis 1962
Lyndon B. Johnson and the Six Day Middle East War 1967
Richard Nixon and the Yom Kippur Middle East War 1973
Gerald Ford and the Mayaguez Affair with Cambodia 1975
Jimmy Carter and the Iranian Hostage Seizure 1979
Ronald Reagan and the Beirut, Lebanon Marine Barracks Bombing 1983
George H. W. Bush and the Iraq Invasion of Kuwait 1990
Bill Clinton and the World Trade Center Bombing 1993
George W. Bush and the World Trade Center and Pentagon Attacks 2001
Barack Obama and the Libyan Consulate Attack 2012
Sadly, politics come into play, and the opposition party always blames the President for the shocking event, as if he has control over factors outside his control.
But that is part of the reality of American politics and history!