"Fox News Sunday" anchor Chris Wallace said some in Washington, D.C. are concerned that President Trump may revoke Special Counsel Robert Mueller's security clearance.

The discussion comes after Trump revoked ex-CIA Director John Brennan's clearance and reports he may be looking to make similar decisions about others critical of his administration.

Wallace said revoking Mueller's clearance would stymie the investigation into whether Trump colluded with Russia.

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He said those who are concerned think it would "stop the investigation without firing" Mueller.

Wallace said Trump likes to choose "foils" he is comfortable sparring with, including Rep. Maxine Waters (D-Calif.) -- who he calls "the leader of the Democratic Party."

He said that in addition to the fiery Brennan, some more reserved criticisms of Trump have come from people like Bush-era intelligence chief Michael Hayden.

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