(CNSNews.com) - The Iranians are watching how President Trump deals with North Korea, and the North Koreans are watching how President Trump deals with Iran, Sen. Lindsey Graham told CBS's "Face the Nation" on Sunday.
President Trump has been very critical of both hard-line regimes, which are in the process of acquiring nuclear weapons.
"2018 will be a year of opportunity and extreme danger," Graham said. "The president has drawn a line in North Korea, telling the regime, I will never let you hit America with a nuclear-tipped missile. If I have to, I will use military force to stop you.
"Now, the Iranians are watching how the way he engages with North Korea, and vice versa. So, we have got a chance here to deliver some fatal blows to really bad actors in 2018. But if we blink, God help us all."
Graham said 2018 is going to be the year when the U.S. denies North Korea the capability to hit the homeland.
"Sanctions will never work completely without the threat of credible military force. How do you change a man's behavior who is willing to kill his own family, torture his own people to stay in power?" Graham asked. He noted that North Korean dictator Kim Jong-un is "living large, and he could care less about his people."
"The only way he will change his behavior is if he believes that Donald Trump would use military force to destroy his regime. And the Iranians are watching how Trump deals with North Korea.”
Graham said he thinks Trump has made "good foreign policy choices," not only in his approach to North Korea, but also on Iran.
In multiple tweets over the holidays, Trump said it's "time for change" in Iran, where the Iranian people "are finally acting against the brutal and corrupt Iranian regime."
"And he is now on the side of the Iranian people,” Graham said. “But he has to do more than watch. He actually has to act. And if I were him, I would withdraw from the nuclear agreement with Iran next year if it's not made better by the Congress and our European allies.”
Graham urged Trump to deliver a nationwide address “explaining why the Iranian nuclear deal is a bad deal for the world, what a better deal would look like, and urge Congress and the European allies to get a better deal with Iran before it’s too late.”
Although Trump has tweeted his support for the Iranian people who are protesting their own government, “you can’t just tweet here," Graham said.
“You have to lay out a plan. And if I were President Trump, I would lay out a plan as to how I would engage the regime. I would tell the Europeans and the Congress and the world that America is going to withdraw from this (nuclear) agreement unless it’s a better deal. And I would lay out what a better deal would look like. And I would stand with the Iranian people the entire time.”