What began as a horrific shooting of two National Guard members in downtown Washington last week has now led to a set of far-reaching changes to the U.S. immigration system.

The suspect, Rahmanullah Lakanwal, was among the Afghans who came to the United States after the Taliban’s takeover of Afghanistan. Earlier, he served in a paramilitary unit that worked with U.S. forces.

Hamed Aleaziz discusses Mr. Lakanwal’s journey to the United States, as well as the Trump administration’s wide-ranging response.

Guest: Hamed Aleaziz, a Times correspondent covering the Department of Homeland Security and immigration policy.

Background reading: The suspect in the shooting had traveled a long path of conflict from Afghanistan to America. Afghans who assisted the United States during the war underwent rigorous vetting.

Photo: The New York Times

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