FEATURE | Houthis' Red Sea blockade could overextend US forces

That could limit what is available for a conflict near Yemen, which officials say would require significant naval and aerial resources, and would divert US intelligence resources, given the need to pinpoint Houthi capabilities that may have changed since last year.

Mark Cancian, a retired US Marine officer at the Center for Strategic and International Studies, agreed that a second front in the Red Sea would stretch US naval forces. But, he added, the Houthis would face their own challenges getting resupplied, given the ongoing blockade of Iran, which has been the group's main supporter.

"The US blockade is not 100 per cent effective but it is highly effective. As a result, the Houthis may be hard pressed to continue a campaign for long," Cancian said.

(Reporting by Idrees Ali and Phil Stewart; Editing by Don Durfee and Kate Mayberry)