Stephen Miller, a senior adviser to President Trump, at the White House on Aug. 16. (Mandel Ngan/AFP/Getty Images)

The Sept. 8 editorial “First, separation. Now, incarceration. ” described Stephen Miller as being among the White House “immigration hard-liners” behind the Department of Homeland Security’s efforts to overturn the Flores agreement and jail migrant children indefinitely.

Mr. Miller is the adviser who, just days after President Trump’s inauguration, helped perpetrate the first executive order aimed at barring Muslim refugees and all others from several predominantly Muslim nations. Pushing “zero tolerance,” he has helped install fellow hard-liners throughout the State Department and has worked to confirm Robert Mortensen as the head of the State Department’s refugee and immigration bureau. Mr. Mortensen’s anti-immigration writings often appear with those of other anti-immigration writers. Last month, Mr. Miller’s uncle, neuropsychologist David Glosser, publicly denounced Mr. Miller as a hypocrite, noting that Mr. Miller’s early-20th-century ancestors arrived as immigrants fleeing pogroms in Eastern Europe.

Tino Calabia, Chevy Chase