Sure. If you want to define terrorism as a subset of activism, then church bombings are like sit-ins in that sense. However, since this is a pretty vacuous truth, my spirit guides tell me that what you really meant to imply was that DDoS'ing corporate websites is an illegitimate, antisocial, unethical, unjustifiable, uncivil form of protest like church bombings are, or since you're very likely going to balk at the hyperbole of the comparison, like G20 looters. Hm! Isn't this implication exactly the question being discussed (as well as the question that you're begging)?
Hey, I've got an idea. Why don't you try to answer that underlying question and establish that it is an illegitimate form of protest like you've been trying to do but without exploiting nebulous definitions and heavy handed comparisons? Maybe you could tell us what exactly condonable protest and civic discourse is in the 21st century and how modern democracy is evolving or devolving and... oh my god we'd actually be touching on the salient and profound lessons to be learned from cablegate and the middle eastern revolts which is actually a very serious topic that warrants somewhat more consideration than some fuckwit kneejerk one line opinion! You'd be in serious danger of having an actual point if you did this.