On This Day: 21 November

1964 – Second Vatican Council: The third session of the Roman Catholic Church's ecumenical council closes.

1967 – Vietnam War: American General William Westmoreland tells news reporters: "I am absolutely certain that whereas in 1965 the enemy was winning, today he is certainly losing."

1969 – U.S. President Richard Nixon and Japanese Premier Eisaku Satō agree on the return of Okinawa to Japanese control in 1972. The U.S. retains rights to bases on the island, but these are to be nuclear-free.

1969 – The first permanent ARPANET link is established between UCLA and SRI.

1970 – Vietnam War: Operation Ivory Coast: A joint United States Air Force and Army team raids the Sơn Tây prisoner-of-war camp in an attempt to free American prisoners of war thought to be held there.

1971 – Indian troops, partly aided by Mukti Bahini (Bengali guerrillas), defeat the Pakistan army in the Battle of Garibpur.

1972 – Voters in South Korea overwhelmingly approve a new constitution, giving legitimacy to Park Chung-hee and the Fourth Republic.

1974 – The Birmingham pub bombings kill 21 people. The Birmingham Six are sentenced to life in prison for the crime but subsequently acquitted.

1977 – Minister of Internal Affairs Allan Highet announces that the national anthems  of New Zealand shall be the traditional anthem "God Save the Queen" and "God Defend New Zealand".

1979 – The United States Embassy in Islamabad, Pakistan, is attacked by a mob and set on fire, killing four.

1980 – A deadly fire breaks out at the MGM Grand Hotel in Paradise, Nevada (now Bally's Las Vegas). Eighty-seven people are killed and more than 650 are injured in the worst disaster in Nevada history.

1985 – United States Navy intelligence analyst Jonathan Pollard is arrested for spying after being caught giving Israel  classified information on Arab nations. He is subsequently sentenced to life in prison.

1986 – National Security Council member Oliver North and his secretary start to shred documents allegedly implicating them in the Iran–Contra affair.

1992 – A major tornado strikes the Houston, Texas area during the afternoon. Over the next two days the largest tornado outbreak ever to occur in the US during November spawns over 100 tornadoes.

1995 – The Dayton Agreement is initialed at the Wright-Patterson Air Force Base, near Dayton, Ohio, ending three and a half years of war in Bosnia and Herzegovina.

1996 – Humberto Vidal explosion: Thirty-three people die when a Humberto Vidal shoe shop in Río Piedras, Puerto Rico  explodes.

2002 – NATO invites Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia to become members.

2002 – Arturo Guzmán Decena, founder of Los Zetas and high-member of the Gulf Cartel, was killed in a shoot-out with the Mexican Army and the police.

2004 – The second round of the Ukrainian presidential election is held, giving rise to massive protests and controversy over the election's integrity.

2004 – Dominica is hit by the most destructive earthquake in its history. The northern half of the island sustains the most damage, especially the town of Portsmouth. In neighboring Guadeloupe, one person is killed.

2004 – The Paris Club agrees to write off 80% (up to $100 billion) of Iraq's external debt.

2006 – Anti-Syrian Lebanese politician and government minister Pierre Gemayel is assassinated in suburban Beirut.

2009 – A mine explosion in Heilongjiang, China kills 108.

2012 – At least 28 are wounded after a bomb is thrown onto a bus in Tel Aviv.

2013 – Fifty-four people are killed when the roof of a shopping center collapses in Riga, Latvia.

2013 – Massive protests start in Ukraine  after President Viktor Yanukovych  suspended signing the Ukraine–European Union Association Agreement.

2014 – A stampede in Kwekwe, Zimbabwe  caused by the police firing tear gas kills at least eleven people and injures 40 others.

[ On This Day]