Former Homeland Security Secretary Jeh Johnson says he is worried about the department under the Trump administration.

“[I’m] very concerned about the direction we’re taking in a lot of national security areas,” Johnson said in an MSNBC interview on Wednesday. “I’m concerned that we’re, when it comes to homeland security, we may be fighting the last war.”

“We may be responding to the terrorist attack of 10 years ago, versus the next one,” he said. “Given where we are right now with the current threat environment, we need to focus on home-grown, home-born violent extremism — just something we did a lot of in the last administration.”

Johnson, who returned to his longtime law firm after Trump’s inauguration, also criticised President Donald Trump’s handling of the travel ban that attempted to restrict travel to the US from six majority Muslim countries. His firm also joined the protests against the White House’s implementation of the revised ban by submitting an amicus brief on behalf of several companies.

“I used to tell my lawyers in the Department of Defence and in DHS, bad facts make bad law,” Johnson said. “And when you bring a case to a court on bad facts, sloppy facts, it’s harder to defend certain basic legal principles.”

“It is the case that the president, the secretary of Homeland Security have considerable legal discretion to regulate our borders, but when you tell a judge ‘My authority in unreviewable,’ almost every judge will say, ‘Oh, we’ll see.'”

Johnson conceded that he had hope in Trump’s ability to govern in the future. “I actually believe that Donald Trump … has the potential to be a great president in sort of the Nixon-goes-to-China way, or Reagan-goes-to-the-Soviet-Union way, if he can find a way to rein in some of the more unhealthy impulses, listen to his staff, bring on a full complement of political appointees who will help him govern,” he said.

“[These] two months can seem like two years, but two months is not a very, very long time. And I hope that there is considerable on-the-job-learning.”

Watch the entire interview below:

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