Matt Olsen, former director of the National Counterterrorism Center under President Obama, stated that Donald Trump’s proposed lockdown of the border would alienate the people we rely on to help us.

“The ban would be wrong in terms of American values and strategy,” Olsen said Friday in an interview with Yahoo Global News Anchor Katie Couric. “I personally wouldn’t think it’s appropriate from just a strategic standpoint to support a policy that alienates the people we rely on to help us, and that is the Muslim American community.”

Olsen, who has been informally advising presumptive Democratic nominee Hillary Clinton, expressed his concern over the presumptive Republican nominee’s proposed ban on all Muslim immigration to the U.S. He added that it was important to build trust with Muslims in the country, seconding President Obama’s attitude that the rhetoric surrounding Islamic extremism and radical Islam is inherently dangerous.

“We can’t paint an entire religion with a broad brush … All religions have some history of violence,” he said. “Focusing on a whole religion will not help stop [the terrorism].”

Olsen reiterated that a need for an all-encompassing ban of this nature is unnecessary because there is a rigorous vetting process to enter the country — people cannot enter America without being checked against a federal database.