The letters may have been sent by agents working for the ADL, for example. They may be trying to use this to stamp out the right-wing opposition. The ADL may use this to pass laws to outlaw conservatism.
Rotfl. What particular mosque do you belong to?
Hopefully, this is a disinformation/diversionary tactic on the part of the "terrorists". BUT, the pattern doesn't look good at this stage. If it is a right wing wacko, the damage to conservatism will be incalculable.
There is no conservative litmus test re: fall on the sword support for Israel. Some, including the Falwell/Robertson's and other conservatives often take the approach of Israel, right or wrong. Others take a more balanced view and believe that while Israel is a closer ally than the Arab & Muslim states, that the interests of the US come first. Still others fall into the anti-Semitic category. The ADL is a sorry group to be sure but I don't think they would be involved in this.
UPDATE: FoxNews just said ~20 members of Daschles office test + for anthrax. Like I said yesterday, time to dust off the nukes. Hopefully we don't have to use them on our own nutcases.