On May 4, 27 Members of Congress, led by Rep. John Conyers (D-MI) and Rep. Ted Yoho (R-FL), sent a bipartisan letter to President Obama urging him to maintain his opposition to the transfer shoulder-fired surface-to-air missiles ("MANPADS") to Syrian combatants. The letter followed a report in the Wall Street Journal that the Central Intelligence Agency was considering supplying Syrian insurgents with MANPADS.

The Conyers-Yoho letter was endorsed by VoteVets, the Friends Committee on National Legislation, and Just Foreign Policy.

Rep. Conyers said:

Our letter shows broad bipartisan congressional opposition to the transfer of MANPADS to Syria. While we may have differing perspectives regarding the appropriate US response to the horrific violence in Syria, we agree that MANPADS would only lead to more violence, not only in Syria, but potentially around the world.

While the CIA was reported to be considering providing MANPADS to Syrian insurgents, administration officials have continued to express deep skepticism of the idea in the press. "It only takes one stray MANPAD to sneak into Turkey and that would be a very bad thing," a U.S. official told the Los Angeles Times. MANPADS can be fired at aircraft by individuals on the ground and can be easily hidden or transported in the trunk of a car. In 2011, a State Department factsheet noted: "Since 1975, 40 civilian aircraft have been hit by MANPADS, causing about 28 crashes and more than 800 deaths around the world."

In June 2014, the House of Representatives unanimously approved a Conyers-Yoho amendment to the Department of Defense Appropriations Act of 2015 that would have prevented the transfer of MANPADS to any party in the Syrian Civil War. Language prohibiting the transfer of MANPADS to Syria was included in the base text of the Department of Defense Appropriations Act of 2016, which passed the House overwhelmingly.

Concerns over the potential for terrorist groups to obtain MANPADS from U.S.-supplied insurgents have been greatly heightened by incidents in which terrorist groups captured U.S.-supplied weaponry in Syria.

In addition to Reps. Conyers and Yoho, the letter was signed by Reps. Seth Moulton (D-MA), Jeff Miller (R-FL), Ruben Gallego (D-AZ) , Walter B. Jones (R-NC), Beto O'Rourke (D-TX), Mark Meadows (R-NC), Henry C. "Hank" Johnson, Jr. (D-GA), Mick Mulvaney (R-SC), Peter A. DeFazio (D-OR), Richard M. Nolan (D-MN), Peter Welch (D-VT), Steve Cohen (D-TN), Ann McLane Kuster (D-NH), Earl Blumenauer (D-OR), Jared Huffman (D-CA), Louise McIntosh Slaughter (D-NY), Alan S. Lowenthal (D-CA), John Lewis (D-GA), Alan Grayson (D-FL), Jim McDermott (D-WA), James P. McGovern (D-MA), Raúl M. Grijalva (D-AZ), Katherine M. Clark (D-MA), David N. Cicilline (D-RI), Nydia M. Velázquez (D-NY).

The text of the letter follows.