As a child, I lived through two wars, and I was exposed to various acts of terrorism. While incidents such as the Oklahama City bombing or the bombing of the World Trade Centre might stand out as highlights, every action, whether it be the government's at Ruby Ridge and Waco or the Ku Klux Klan's in the name of White Supremacy, that uses systematic violence as a means of coercion is terrorism. I abhor violence. I don't think violence solves any problems. This is not to deny that at times violence does provide a therapeutic or cathartic release, or even treat a problem, but it doesn't offer a cure.
Terrorism is usually about making a statement.
Both end up making a statement about their ideologies, and both end up killing innocent people. However noble their goals might be, in either cases, their actions are unjustified. Draconian security measures are not the answer to the problem. I think it is impossible to prevent terrorist acts from happening, if someone really wants to do it. Sure, we can always punish the perpetrators, but that is not a solution.