CHICAGO (CBS) — President Donald Trump said his goal through signing the seven nation travel ban was to keep “radical Islamic terrorists” out of the United States. A new report from a University of Chicago think tank says his ban attacks a problem that doesn’t exist.

CBS 2’s Derrick Blakley reports.

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The new report is called “The American Face of ISIS.” It studied 104 defendants indicted by the federal government for Islamic State-related crimes. The paper also looked at eight others who died in service of ISIS.

Of the studied defendants, 65 percent were U.S. citizens by birth. 30 percent were converts to Islam. Only three were refugees, one from Iraq and none from Syria.

DePaul University terrorism expert Thomas Mockaitis reviewed the study, and said it confirmed his thoughts.

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“These are not refugees coming in to attack us. These are, by and large, people born in the United States, many of whom are converts to Islam and don’t fall even into the typical ethnic groups you would expect to be Muslim,” he said.

Nearly all of the suspects were led to ISIS by powerful online propaganda videos. University of Chicago Prof. Robert Pape said terrorists know they cannot confidently get through immigration controls.

“What they’re doing is not trying to smuggle something through. What they’re doing is jumping over them with their propaganda,” he said.

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Pape thinks the Trump travel ban could feed the ISIS propaganda machine. The measures could reinforce the theme that America is fighting against Islam and not just terrorists.