Former U.S. Sen. William S. Cohen of Maine served in the wedding party of his friend John McCain at the then-Navy captain’s marriage 38 years ago.

In a few days he will serve as a pallbearer at the funeral of Sen. McCain, who died Saturday at age 81 after a battle with brain cancer.

On Sunday Cohen, also a former Republican U.S. House member from Bangor and secretary of defense in the Clinton administration, spoke at length about his longtime friend.

“What most impressed me about him was his passionate patriotism,” Cohen said in a telephone interview. “He only thought about doing what was right for the country.”

Cohen said he had made some comments on videotape months ago for CNN when McCain’s brain cancer was first announced, to be used in the event of McCain’s death. The tape ran Sunday on the cable network. But for most of Sunday, Cohen said he avoided the media, wanting the day to reflect, until he couldn’t contain his thoughts any longer.

In the telephone interview with the Press Herald, he recounted fond memories of his enduring friendship with McCain.

He said he first met McCain in 1978 during a trip to China to meet that country’s then-leader, Deng Xiaoping. Cohen was a senator-elect at the time and McCain was the Navy’s Senate liaison officer escorting Cohen’s group. When McCain learned that Cohen had failed to select the Senate Armed Services Committee to serve on, he respectfully badgered him to change his choice, even though that meant Cohen had to personally call the chairman of the Judiciary Committee and tell him about his new plans.

“He was so persistent,” Cohen said.

But if McCain had not persisted, Cohen said he probably never would have wound up on the Armed Services Committee or ultimately be appointed secretary of defense.

He also recalled McCain’s “peripatetic” lifestyle.

“He traveled the world relentlessly. He never stopped moving. I don’t recall anyone with his sense of energy, drive and enthusiasm to do well for the country and do well for the world,” Cohen said.

Cohen said he tried to capture some of McCain’s personality in his series of thrillers featuring the fictional former senator and national security adviser Sean Falcone, the latest of which, “Final Strike: A Sean Falcone Novel,” was published in February.

“Someone of great conscience and trying to do what is right, understanding that he was imperfect as well,” Cohen said, describing both the fictional character and McCain.

He said he would sometimes call McCain “Sean” and McCain would starting grinning.

“He is actually better than Sean. He was the real deal. John McCain was the real thing,” Cohen said.

Cohen cited several incidents in McCain’s life that illustrate his friend’s integrity.

He said it took him more than three years of pressing to get McCain to share his experiences during the 5½ years he was held as a prisoner of war in North Vietnam.

“When you think about what he went through, five years, all of the broken bones, all of the torture, the fact that he led the effort to reconcile with Vietnam spoke volumes about his character,” Cohen said.

He also cited the time McCain defended Barack Obama during the 2008 presidential campaign after a woman called Obama “an Arab.”

“Now most other politicians wouldn’t have done that,” Cohen said. “They would have catered to the anger and bigotry.”

Cohen said McCain was born to fight.

“His entire life he was a fighter and he fought this until the end,” he said, referring to the brain cancer. Earlier, “he had a tremendous battle with skin cancer, went through multiple operations. Very few people would have survived that, but he did, and then to think he had an aneurysm and comes back to the Senate.”