Officials in Saudi Arabia, the region's Sunni Muslim power, say the air campaign is dealing a decisive blow against the Houthis, whom they view as tools of aggression used by Shiite Muslim-led Iran in an expanding proxy war....However, residents say the strikes have done little to reverse the territorial gains of the insurgents and restore exiled President Abdu Rabu Mansour Hadi to power in the quickly fragmenting country.

....Security experts question whether the coalition can achieve its goals through airstrikes alone. Saudi officials have not ruled out sending in tanks, artillery and other ground forces massed along the frontier. But Saudi leaders appear wary of such a move against the Houthis, hardened guerrillas who belong to an offshoot of Shiite Islam known as Zaidism.

The last time the Saudis fought the Houthis in the rugged mountains of northern Yemen, in 2009, more than 100 of their men were killed. Pakistan's parliament voted Friday to stay out of the conflict, a blow to the Saudis, who had reportedly asked the country to send troops, fighter jets and warships.

"This [war] will turn Yemen into Saudi Arabia's Vietnam," said Mohammed al-Kibsi, a veteran journalist and commentator in Yemen's capital, Sana, where the Houthis seized control in September.