Since the JCPOA was signed on July 14, a variety of group statements have been issued, including from veteran national security leaders, retired top military officials, scientists and nuclear experts, etc. The most important of these letters are included below.
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8/31: 74 Prominent Iranians Urge Congress to Support Nuclear Deal with Iran
8/31: Growing List of U.S. Rabbis (440 and counting) Urge Congress to Support Nuclear Deal with Iran
8/31: 71 Former Senators and Representatives Urge Congress to Support the Iran Nuclear Agreement (text of statement here)
8/29: Majority of DNC Delegates Sign Letter to Obama in Support of Iran Deal
8/27: 70 national organizations (including APN) Implore Congress to Support Iran Deal
8/27: 11 Jewish ex-lawmakers call on Congress to back Iran deal (text of New York Times ad is here)
8/24: Letter from more than 50 Christian leaders supporting the Iran deal (Politico article here)
8/20: 26 Former Jewish Leaders Call on Congress to Approve Iran Deal (text of and full list of signers is here)
8/17: Statement from 75 Nuclear non-proliferation specialists in support of the Iran deal
8/16: 340 Rabbis Urge Congress to Support Nuclear Deal with Iran
8/12: 98 Prominent Hollywood Jews Back Iran Nuclear Deal in Open Letter (including text of letter & list of signers)
8/11: Dozens of retired generals, admirals back Iran nuclear deal -- Text of letter here
8/8: 29 U.S. Scientists Praise Iran Nuclear Deal in Letter to Obama -- Text of letter is here (# of signers as of 8/12/15 is 32).
8/3: US Steelworkers (USW) Voices Support of Proposed Nuclear Agreement with Iran
7/24: European Leadership Network members express support for the Iran nuclear agreement - Group statement signed by over 70 members
7/22: U.S. Council of Catholic Bishops (USCCB) Urges Congress to Support Iran Deal