( CNN) Two weeks before she was fired, Kirstjen Nielsen told President Donald Trump “no.”

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Trump eventually scrapped the idea — although he floated the idea of closing the entire US-Mexico border via Twitter soon after. Eventually he gave up on that notion as well.

Nielsen joined a surprisingly long listing of White House aides who told Trump “no” when he asked them to do something that they believed was either illegal, politically perilous — or both. Not coincidentally, all of the people who told Trump “no” don't work for him anymore.

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