North Korea has been threatening world peace by defying calls to give up its nuclear weapons development programme.
Mr Morey said: “There is no good option when it comes to North Korea. You can’t ignore them, starve them, destroy them or even negotiate with them.
“Destroying them would involve – some people think – a trillion dollars and a million lives within the first days of a conflagration on the peninsula. So there’s no good option.”
The public diplomacy expert said it was “unrealistic” to think sanctions on North Korea would ultimately dash Kim Jong-un’s nuclear ambitions.
But he said stepping up the US and South Korea’s diplomatic approach to the North Korean issues could prove to be the best solution for a peace treaty with Pyongyang.
Speaking to Fox News, Mr Morey said: “What we have to do is get really smart, get realistic. It’s unrealistic the sanctions alone will solve the problem.
“It’s also unrealistic to get North Korea to give up its nuclear weapons given the rationality of that administration. I think we gotta take steps to freeze their nuclear weaponry, de-escalate tension, create a moratorium and eventually – if they did all that – there would be room for a treaty between South Korea, North Korea and the United States.”
In November 2017, North Korean defector Thae Yong-ho also warned about the “huge human loss” a conflict with North Korea would cost to all parties involved.
The former diplomat said Pyongyang had trained its soldiers to “fire back in any way” in the event of an attack.
He said: “I think even a limited strike by the US can bring a full-scale conflict on the Korean peninsula because all of North Korea’s military has been trained to fire back in any way.
“Even if a small part of North Korea is attacked by the US – given the fact that more than 10 million of the South Korean population lives in a 100-miles range of North Korean artillery and missiles – I think that immediate and automatic response from the North Korean military can create huge human loss on the South Korean side.”
North Korea has so far failed to heed calls to denuclearise and enter diplomatic talks with the US or neighbouring South Korea.
Instead, leader Kim Jong-un started an escalating war of words with US President Donald Trump – warning Mr Trump with claims of a “nuclear button” on his desk ready to be pressed.