House Democrats failed Thursday to pass a war powers resolution that would constrain President Trump's ability to wage war with Iran.Why it matters: It is the third time Democrats have tried and failed to pass an Iran war powers resolution, which some lawmakers fear will be seen as a green light to the Trump administration to keep ignoring Congress.The measure, introduced and forced to a vote by House Foreign Affairs Committee ranking member Greg Meeks (D-N.Y.), failed 213 to 214.What happened: Centrist Rep. Jared Golden (D-Maine) voted with Republicans against the measure, while libertarian-leaning Rep. Thomas Massie (R-Ky.) voted with Democrats to pass it.Rep. Warren Davidson (R-Ohio), who voted to pass an Iran war powers resolution last month, voted "present" on Thursday.Reps. Juan Vargas (D-Calif.), Greg Landsman (D-Ohio) and Henry Cuellar (D-Texas), who voted against the measure last month, flipped and voted for it.