For a man who goes on Twitter rants at 3:00 AM, and has built a base of supporters by way of his tell-it-like-it-is, unfiltered and unplugged speeches, Donald J. Trump—at least when it comes to foreign policy—puts a premium on discretion and secrecy.

“Well, all of these bad leaders from ISIS are leaving Mosul. Why can't they do it quietly? Why can't they do the attack, make it a sneak attack, and after the attack is made, inform the American public that we've knocked out the leaders, we've had a tremendous success?" Trump asked of American military leaders at the last presidential debate. "People leave. Why do they have to say we're going to be attacking Mosul within the next four to six weeks, which is what they're saying? How stupid is our country?“

Juliette Kayyem, homeland security expert and host of the "Security Mom" podcast, says there are quite a few specific reasons why.

“”There’s a reason why the defense department is clearly signaling a potential attack," she said. "It’s to protect civilian life, it’s a form of propaganda, and its what we did in other advancements in this war against ISIS, let alone in other wars."

"It’s also because we take a premium in wars like this in which the enemy has infiltrated the civilian apparatus," she continued. "It’s not like there’s a bunker called 'ISIS' we can just bomb—and, to be honest, when we find it, we do bomb it. They are integrated into the civilian population and we’ve got to warn the civilian population to get out while they can."

To hear more from homeland security expert Juliette Kayyem, tune in to Boston Public Radio above.