Give me a break.
"Some group has the scientific sophistication to weaponise anthrax spores,"
1. Assumptions: the group made it, rather than was given a little by a state or puchased it from the state or "black market"
"harnessing for themselves WMD-scale destructive power close to atomic weaponry, and what do they do?"
2. Well, I don't think it's close to atomic scale, and they didn't have a lot.
"Attack some tabloid which has published sexy photos of Jennifer Lopez, all because they don't like the way JLo shakes her booty?"
3. Well, they did attack a tabloid, didn't they? As for J.Lo, why not? And consider whether the sender had different objectives and interests than the hypothetical mastermind we assume would think bigger.
Also, assume this: if one wanted notoriety, along with network anchors whom else would one target?