DETROIT, Mich. — Following the recent Democratic presidential debate in Flint, Bernie Sanders was approached by a Syrian refugee who wanted to ask the candidate a question about the nation he left.

Sanders initially was open to answering a question, but upon hearing the query was about Syria, Sanders brushed the man aside, saying he was “tired.”

His refusal to allow a Syrian refugee to even pose a question is just the latest episode illustrating his disinclination to talk about national security matters.

Sanders has demonstrated a relatively poor understanding on foreign policy, especially when compared side-by-side with former Secretary of State Hillary Clinton. When he does talk about the issue, it often comes out sounding nonsensical, like when he proposed longtime enemies Iran and Saudi Arabia team up to fight ISIS.

The questioner, Ismael Basha, attended the debate as a guest of CNN, the sponsor of the event. After the on-air questioning was completed, he approached the senator from the left side of the stage and greeted him, asking if he could pose a question.

Sanders was happy to take a question, Basha said—until the refugee mentioned that the question would be about Syria, causing Sanders to grimace and raise his eyebrows.

“He had this look—he reacted like it was an unpleasant surprise,” Basha told The Daily Beast. “[Sanders] said, ‘Look, this is not the time, and I am very tired.’”

Basha had been asked to attend the debate by CNN to potentially ask Sanders and Clinton about America’s policies on Syria. But ultimately the network decided not to focus on foreign policy as a line of questioning, so as someone who was planning to vote in the Democratic primary a few days later, he tried to pose the question to Sanders personally.

“My impression is that he’s a genuinely nice guy. But being a nice guy doesn’t make him a great leader,” Basha said. “He is wrong and he doesn’t understand the world well. When he said he was tired, that confirmed my view—this isn’t something he wants to deal with.”

Sanders has focused on domestic policy far more than his foreign policy, something that even he admitted during the debate in Flint. “Secretary Clinton says I’m a one-issue person, well, I guess so,” he said. My one issue is trying to rebuild a disappearing middle class.”

Sanders’s campaign did not respond to a request for comment.

More than a quarter-million people have died in Syria’s civil war; and more than 6 million people have been displaced, half of them children.

Mona Jondy, the government relations chair for advocacy group United for a Free Syria, was also at the Democratic debate in Flint, and was appalled when Sanders’s reaction was recounted to her.

“In a time when the world seems to be burning, and all of our traditional rivals are coalescing to make Syria a launchpad for further expansionism, we simply cannot afford to have a commander in chief who is too tired to talk about it,” Jondy said. “The U.S. president can no longer let this wound fester as we approach a half a million dead, terrorist groups and our state rivals gaining momentum. Ignoring Syria and all the killing won’t just make it go away.”

As a young engineering student at the University in Damascus with outspoken political views, Basha fled Syria in 1979 to escape potential interrogation and imprisonment. He bounced around the Middle East, through Lebanon, Jordan and Egypt, before finally arriving in the United States in 1983. He is now, along with his wife, active in efforts to resettle Syrian refugees in the greater Detroit area. He also owns a manufacturing business in Michigan.

“I consider myself very lucky to have escaped the unbelievable amount of brutality that other Syrians have endured since the 1970s,” he says.

And if CNN had allowed him to ask a question to Sanders on Syria during the debate? Here’s what he would have asked:

“You have advocated that the United States should stay out of the conflict in Syria despite the fact that hundreds of thousands have lost their lives and millions displaced in a very small country—how would you have liked if someone had advocated during World War II not to intervene in the slaughter of Jews?”

Basha never got an answer to his question.

But he voted for Hillary Clinton.