"What we need to do is ensure that we don't create an environment that puts us on a track conceivably where the United States military finds itself in a civil military crisis with a commander in chief who would have us do illegal things," Allen said. | Getty John Allen predicts 'civil military crisis' if Trump is elected

The election of Republican Donald Trump as president could mean a breakdown in the relationship between civilian and military leaders, a former top commander of U.S. forces in Afghanistan warned Sunday.

In an interview on ABC's "This Week," retired Marine Gen. John Allen criticized Trump for his rhetoric on the wider use of military force and torture. And if Trump followed through with those pledges, Allen said, it would create "a civil military crisis, the like of which we've not seen in this country before."


"It's an inherent responsibility in who we are," Allen said. "So what we need to do is ensure that we don't create an environment that puts us on a track conceivably where the United States military finds itself in a civil military crisis with a commander in chief who would have us do illegal things."

"That's a major issue that we're facing here, the potential for a civil military crisis where the military could be ordered to conduct illegal activities," he added.

But Allen, a supporter of Hillary Clinton who spoke at the Democratic National Convention in Philadelphia, said he hoped it wouldn't come to a public feud between military leaders and a Trump administration.

"My hope would be that the conversation would occur quietly in the Oval Office, or somewhere else, to advise him not to continue along this track," Allen said.

Allen, who also served as President Barack Obama's special envoy to the counter-Islamic State coalition, slammed Trump's pledge to forge better relations with Russia and leverage its support for the campaign, adding that Russia's conduct in Syria isn't helping in the fight against the Islamic State.

"They drop dumb bombs," Allen said of Russia. "So when we talk about carpet bombing ISIL, that's what it looks like, creating huge numbers of civilian casualties, which increases the numbers of refugees flowing out of the region, which increases the misery of the Syrian people.

"Russians haven't helped us," he said.

Allen also deflected criticism from Trump, who dismissed him as a "failed general" in response to his Democratic convention speech criticizing the Republican's national security stances.

"He has no credibility to criticize me or my record or anything that I have done," the retired four-star general said. "If he had spent a minute in the deserts of Afghanistan or in the deserts of Iraq, I might listen to what he has to say."