John Hudson reports on the “information war” between Israel and the U.S. in Congress:

All week, the Obama administration has provided facts and figures to lawmakers on its sanctions relief proposal to build support for a deal on Iran’s nuclear program. But some members in Congress don’t trust the data U.S. officials are providing — they trust conflicting data provided privately by senior Israeli officials.

The differences between U.S. and Israeli claims aren’t all that remarkable. The notable thing in this story is how eagerly credulous some members of Congress are in accepting information from another government whose desire to block a deal is obvious. The information provided by Israeli officials overstates the extent of sanctions relief, but then one would expect Israeli officials to exaggerate how much Iran is “getting” out of any deal. The only reason to prefer the information coming from Israeli officials in this case is if these members of Congress are already dead-set against a deal and are looking for some minimally plausible excuse.

Kirk claimed to be annoyed when he was told to discount what he was hearing from Israeli officials, but given his views on sanctions and Iran it is extremely unlikely that he would change his position on additional sanctions even if he accepted the administration’s numbers. It makes no difference to vehement opponents of sanctions relief what the amount happens to be, since they are against any and all sanctions relief.

Besides the government’s obvious hostility to a deal, there is good reason to doubt the accuracy of the Israeli claims. Hudson writes:

Other arms control experts were puzzled as to why the Israeli assessment gained any traction at all over the American assessment — since Israelis are not members of the so-called P5+1 countries negotiating a deal with Iran.

“Personally, I would tend to believe the estimates and figures of the people who are actually at the negotiating table rather than people that are getting this information second-hand, even if they’re senior Israeli officials,” Daryl Kimball, executive director of the Arms Control Association, told The Cable. “This is in many cases a distortion of the physics and the reality.”

It’s not all that puzzling. Some members of Congress hope that diplomacy with Iran goes nowhere, and they will sooner trust information from a government that wants to wreck negotiations than from the one trying to reach an agreement.