Former U.S. Attorney General Michael Mukasey on Friday pushed back at criticism of the National Security Agency’s surveillance operations, saying he trusts that the NSA is lawfully gathering information.

Mukasey, who led the U.S. Department of Justice under President George W. Bush from 2007 to 2009, said he believes the probability is low that the NSA would do anything but work to protect the United States from terrorism, when the agency knows that Americans would hold the agency accountable for a terrorist attack.

“What would be the point of gathering information for recreational use or gathering information for any other use than protecting the country when the thing that [Americans] most fear is an attack on the United States?” he asked at the Federalist Society’s National Lawyers Convention, an annual Washington, D.C., gathering of conservative attorneys.

Since former NSA contractor Edward Snowden’s revelations earlier this year about the agency’s far-reaching access into user data held by technology companies, it has faced a barrage of criticism from the tech industry, which has urged the U.S. government to be more open about the information it collects.

President Barack Obama’s administration pledged in September that it would annually publish the total number of national security demands for customer data. But Microsoft Corp., Google Inc. and other tech businesses are at the U.S. Foreign Intelligence Surveillance Court, the secret court that oversees the NSA’s programs, fighting for more transparency. The companies have said they’re seeking consent to publish the number of national security demands they receive and the amount of user accounts affected.

Although Mukasey didn’t address the companies’ requests, he said the government should give “acceptable descriptions of [intelligence] programs that do not disclose operational details or do not disclose them in sufficient detail for them essentially to defeat themselves.” But much of the government’s intelligence gathering operations need to remain opaque to the public, he said.

“Otherwise, ain’t no point in having it,” Mukasey said.

The former attorney general also said he was wary of reforms to the NSA’s approach to surveillance, taking particular issue with calls for an advocate to challenge and take the other side of anything presented to the Foreign Intelligence Surveillance Court. Critics of the court have called it a “rubber stamp” for the NSA, saying the lack of an adversary during court proceedings on intelligence gathering is problematic.

“I hate to hark back to people who were associated with the Nazi government during World War II, but every time I hear the word ‘reform,’ I reach for my revolver,” Mukasey said.