I disagree. However, nobody wants to admit that their team did evil things, so we whitewash. Very rarely do people see anything but black and white when it comes to 'Us vs Them' situations.
Then you are extending the definitions of "terrorist" and "terrorism" to such broad lengths as to make the terms useless for anything except political and propaganda purposes. It has nothing to do with admitting to or denying evil things.
Terrorism is political violence, but not all political violence is terrorism. Terrorists use political violence to further their ends, but not everyone who uses political violence is a terrorist.
Terrorism is political violence, but not all political violence is terrorism. Terrorists use political violence to further their ends, but not everyone who uses political violence is a terrorist.