Did American leaders lie in order to invade Iraq?

Answer 1

No.

The Central Intelligence Agency received intelligence that Iraq had access to "Weapons of Mass Destruction". This information was reported to President Bush, who had it redirected to the UN and NATO.

The UN gave an order for inspectors to go investigate the claims, but the Iraqi leader, Saddam Hussein, refused to cooperate. In response, UN/NATO had to make a decision on how to handle Saddam's refusal, and it was decided that Saddam's past aggressions made him untrustworthy, and that even the slightest possibility of him having heavy weaponry was a threat to national security.

It was decided that Saddam was a threat and needed to be removed before he used the weapons to invade his neighbors.

These weapons were never recovered. Why they weren't recovered is debatable. Some believe that Iraq never had access to WMD's, while some believe that Iraq managed to conceal them and sell them off last minute.