US, May 4 -- Just as the United Arab Emirates was beginning to restore normality to its aviation sector, a new Iranian missile strike has cast serious doubt over whether the country's long-awaited reopening of airspace can hold.

Hours after authorities signaled a return to near-full operations at major hubs including Dubai International Airport and Abu Dhabi's Zayed International Airport, air defenses intercepted multiple projectiles targeting the UAE the latest in a string of escalations that have repeatedly disrupted travel across the Gulf.

While officials say there were no major casualties and most threats were neutralized, the timing could hardly be worse.

A fragile reopening for Emirates Airlines and Etihad Airways In recent days,...