Because of worries that terrorists could take advantage of such chaos, FEMA now must abide by post-9/11 security procedures, such as putting air marshals on flights. That meant stranded residents couldn't be evacuated from the New Orleans airport until FEMA had rounded up dozens of Transportation Security Administration screeners and more than 50 federal air marshals. Inadequate power prevented officials from firing up X-ray machines and metal detectors until the government decided evacuees could be searched manually.