President Trump's refusal to commit to a peaceful transfer of power if he loses November's presidential election is a "gift to our adversaries," Trump's former national security adviser H.R. McMaster said Sunday.

The big picture: McMaster, a retired three-star general, said that the American people must understand that the military will have "no role" in a presidential transition, and that it's "irresponsible" to even talk about it as a possibility.

What he's saying: "What I think is it’s a gift to our adversaries who want to shake our confidence in who we are, shake our confidence in our democratic principles and institutions and processes,” McMaster told NBC’s “Meet the Press" about Trump's comments.

• “If the Russians can just use our words against us, that’s the best the best way to pull us apart from one another.”
• McMaster said that he "absolutely" agrees with Susan Rice, former President Obama’s national security adviser, who recently opined in the NY Times that the political division in the U.S. should be treated as a national security threat.

The bottom line: "I think it’s so important for us to come together for civil discussions about the challenges that we face," McMaster said.

• "Maybe that’s a way for us to come back together as Americans because as we’re at each other’s throats with this vitriolic partisan discourse, our adversaries haven’t stopped, the world hasn’t gone away."
• "And that’s what I hope will help galvanize us to come back together and reverse this polarization that is so damaging to our security and our psyche as well."