The bombing of OKC and the Boston Marathon were both acts of domestic terrorism.
9/11 was an act of foreign terrorism.
The school shootings and such are acts of mass murder in my opinion.
In a nutshell:
To be a terrorist one must use violence as a part of a defined, organizes, and publicly expressed political movement.
To commit an act of terrorism one must target and attack an unarmed or noncombatant third party in order to exert pressure on the party against whom the terrorist demands political action.
McVeigh fails on both counts.
McVeigh was a crazy mass murderer and a delusional insurgent, but not a terrorist.
