"If the airstrikes continue outside the context of an overall political settlement, Yemeni opposition to the coalition will harden, not just among the Houthis but among average Yemenis," Des Roches said at an event sponsored by the National Council on US-Arab Relations.
Des Roches warned that without an inclusive political settlement in addition to the military operation Saudi Arabia and its partners "may find that what they thought was a proxy war with Iran will transform into an actual war with Yemen."
"As the air campaign grinds on…its effectiveness will decrease not arithmetically but exponentially," Des Roches noted.
Missile depots, aircraft hangars, runways and other military targets have already been destroyed by the Saudi-led alliance. But other targets may be dispersed among civilians or in areas such as mountain valleys where such targets can be defended by anti-aircraft artillery traps, he warned.
The United Nations has reported approximately 100 civilian casualties and more than 350 civilians injured in the course of the Saudi-led military efforts.
According to reports given to Sputnik, the coalition is mounting an assault on the Gulf of Aden, where Houthis currently maintain control. Saudi and Egyptian ships have been deployed, along with air assets, but there have been no confirmed official reports of a ground operation.
On March 25, an international coalition headed by Saudi Arabia launched a military operation against Houthi positions in Yemen following a request for military support from Yemeni President Abd Rabbuh Mansur Hadi.
