Overall, 43% of Americans support the deal. This falls short of a majority, but supporters significantly outnumber opponents of the deal, who make up 30% of the public. Fully a quarter of Americans (26%) are undecided, however.
Support for the deal falls along familiar political lines. 60% of Democrats back the agreement, which could mark a major legacy acheivement for a Democratic president. 55% of Republicans oppose the deal. Yet Republicans are more likely to support the Iran deal (28%) than Democrats are to oppose (13%), and independents are narrowly in favor (38-31%) with 31% undecided.
Americans also tend to think Iran, not the U.S. and its allies, got the most out of the deal, by 38% to 11%. 20% say both got about the same amount – the “win-win” described by Iran’s foreign minister after the deal was announced.
If Iran breaks the agreement and begins developing a nuclear weapon, majorities of nearly all political and demographic groups say they would approve of the US and its allies taking military action against Iran. Overall 64% say they would approve of using military force in this event, against only 18% who would disapprove.
And if public confidence in the deal is an indication, support for military action may soon be tested. Only 23% of Americans are even somewhat confident the deal will prevent Iran from developing a nuclear weapon, while 27% are “not so confident” and another third are “not confident at all”.
These numbers are consistent with findings before the agreement was announced that showed Americans in favor of negotiations but also distrustful that Iran would keep up with their end of a bargain.