The 'War Against Terror' is still ongoing, so, not enough, it would seem.
These statistics are not keep but I could confidently say more people were killed by police then Americans killed by terrorist or the wars on terror
Because terrorist and terror organizations are located in many locations around the planet.
The "War on Terrorism" is the war going on between the United States and the Taliban (a terrorist organization). There are many links provided with useful information.
Germany invaded and occupied Greece in WW 2 prior to attacking Russia. They bombed Athens and other Greek cities and killed many civilians as part of their terror campaign against the nation.
See: List of terrorist incidents & List of ongoing conflicts
4000 US soldier died in 9 years. the terrorist in Iraq and Afghanistan lost about 2 million.
41,594 people were arrested and killed during the French Reign of Terror, which lasted from September 1793 to July 1794. The executions finally ended when the architect of the terror, Maximillian Robespierre, was overthrown and executed.
In the Munich Olympics there were terrorist that came to the competetdors hotel. The concierge headed them to the wrestlers room (hoping they would be strong enough to take the terrorist). But, the terrorist had guns so many people were killed.
It was called the Big Purge. Stalin's reign of terror is referred to as the Great Terror or the Great Purge.
There were 11 people killed by the Black September groud. All of which were the athletes that they held hostage. Watch the movie "One Day In September"...
The U.S. killed Bin Laden because he was a leading terrorist mastermind whose actions caused great death and suffering to that country and many other nations as well.
Near 190 people died in the Pentagon during the September 11, 2001 terrorist attacks.