Executing someone and blaming others to justify it is not a new terror tactic.

In 1972, the Palestinian Black September terrorist group used the Munich Olympics (search) to draw the world's attention when it took nine Israeli athletes hostage and killed them all during a rescue attempt by German troops.

Six months later, members of the same group executed three diplomats, two Americans and one Belgian, during a hostage crisis in Khartoum, Sudan.

A Lebanese Shiite group calling itself Islamic Holy War in 1985 killed William Buckley (search), the CIA's station chief in Beirut, calling the murder "revenge" for the blood of its own martyrs. Buckley was reportedly tortured for months.

Later that year, the Palestinian Liberation Front hijacked the Italian cruise ship Achille Lauro, executed Leon Klinghoffer (search), an elderly American in a wheelchair, and threw his body overboard.

In 2002, Wall Street Journal reporter Daniel Pearl (search) was beheaded and mutilated in Karachi, Pakistan, while researching a story into convicted "shoe bomber" Richard Reid. His captors needed a reason for the killing, so they first accused him of being an Israeli spy, then an American spy — with no evidence of either.

A group calling itself the National Movement for the Restoration of Pakistani Sovereignty claimed responsibility for Pearl's kidnapping and murder. A British-born Islamic radical named Omar Saeed Sheikh was convicted of masterminding the operation. Some information suggests Al Qaeda leader Khalid Shaikh Mohammed (search), later captured in Pakistan, may also have been involved.

In the latest example — the beheading of 26-year-old Nick Berg in Iraq — the killers stated that their actions were payback for the treatment of Iraqi prisoners at the U.S.-run Abu Ghraib prison outside Baghdad. The masked men also claimed to be acting with Abu Musab al-Zarqawi, the Jordanian believed to be the top Islamic terror leader in Iraq, but offered no evidence of that.

But that doesn't explain why Iraqi insurgents executed an Italian hostage in April, or why four American civilian contractors were killed in Fallujah, Iraq, their bodies burned, dragged through the streets and hung from a bridge by a mob on March 31.

Experts believe the Berg murder really had nothing to do with the Iraqi prisoner abuse story and everything to do with shocking the world and attempting to change public opinion.

Click here to watch a report by Fox News Channel's William LaJeunesse.