The revised travel ban could cause a hit to the tourism industry upwards of $18 billion over the next few years, Reza Marashi, National Iranian American Council research director, said in an interview on CNBC’s “Squawk on the Street.” Marashi said the U.S. government must balance its national security concerns with the economic and humanitarian costs of the travel ban. After 9/11, the tourism industry took a $600 billion hit, and after the travel ban the industry will take another hit, he said.