Yes, I feel strongly that they should be suspended. The damage done by public terrorist propaganda far outweighs the damage of not being able to easily analyze their social graph.

Mind you, there are other ways (not available to anyone with access to the Twitter API) to plot terrorist social graphs.

Those who share or are confronted with terrorist propaganda on social networks are not all terrorists. There is a lot of noise. Forcing the terrorists/propagandists underground, separates the wheat from the chaff. Terrorist propagandists know the value of social networks. They do not use them to plot attacks (at least the smarter ones), they solely use them to brainwash naive youth and recruit them for their cause. I feel Twitter is obligated to combat this. Having a lot of users is no excuse for manual and automatic suspension of people sharing dangerous materials.

I do agree that there is a slippery slope: Do we also suspend those who share information and videos from the war front in Syria? Or only those sharing infographics on poisons or glorification of the Paris attacks? Is blocking terrorist propaganda even censorship or just common sense (criminal negligence to keep it up)?

The constant bombardment of war front posts in your timeline is definitely riling up people to go fight a war that is not theirs. Can we solve this problem, while largely keeping free speech intact, or is free speech always a binary issue?

Also compare Twitter with the older ISP's. You'd have a hard time hosting your own site with terrorist propaganda, while nowadays these social networks give you an easy platform to reach many people.