The first thing U.S. Sen. Lindsey Graham would do as president of the United States is rebuild the nation’s military and intelligence community “so that we could actually engage the enemy.”

The South Carolina Republican, who is considering a run for the White House, sat down for an interview with The Denver Post Wednesday alongside fellow senator and former presidential candidate John McCain.

“At the end of the day, we have to keep them on the run, small and poor,” he said of the militants loyal to the Islamic State, who have grabbed wide swaths of territory in Iraq and Syria in the past year. “Right now they’re large, entrenched and rich.”

McCain, an Arizona Republican, touted his colleague’s military experience as a lawyer and judge with the Air Force Reserve — which has taken Graham to Iraq and Afghanistan for duty on numerous occasions — as the perfect credentials for the Oval Office.

“He has a degree of understanding of the issues and the people in the military that I don’t think anybody else has,” McCain said.

The interview, which took place inside the exhibit halls of the Counterterrorism Education Learning Lab (CELL) in Denver, was a prelude to a talk on how to confront violent extremism the two senators were to give that evening at the Ellie Caulkins Opera House.

The talk was hosted by CELL and The Denver Post.

“The nightmare marriage is between radical Islam and weapons of mass destruction, so the goal of our generation is to make sure that radical Islamic groups, Sunni or Shia, never aquire weapons of mass destruction,” Graham said. “The only reason 3,000 of us died on 9/11 — and not 3 million — is they couldn’t get the weapons to kill 3 million of us.”

McCain cautioned that the power of social media as a terrorist recruitment tool is turning into one of the country’s biggest challenges.

“There are young people today, many of them don’t own a television set,” he said. “They get all their information online. We’re seeing this influence on some young Americans that astounds us.”

In the past year, four teen girls from Colorado have been apprehended after the discovery of what authorities say were plots to go to the Middle East to provide support to al-Qaeda and the Islamic State. Much of the inspiration for their actions came from the Internet, authorities say.

Graham, who serves on the Senate Armed Services Committee with McCain, said there is an opportunity to use the twin threats of expanding Iranian power and the rise of the Islamic State to bring Arabs and Israel closer together in a “regional coalition” to fight common enemies.

Just as critical, he said, is a need for Muslims worldwide to condemn the radical fringe of their religion that casts the entire faith in a negative light.

“Their faith is in jeopardy here,” Graham said.

“Take this romantic lore away from these guys. They need to fight for their faith.”

John Aguilar: 303-954-1695, jaguilar@denverpost.com or twitter.com/abuvthefold