Ted Cruz is getting advice on foreign policy from one of America's most prominent proponents of fear and hate against Muslims: Frank Gaffney. The head of the Center for Security Policy think tank and a former Reagan administration official, Gaffney helped coin the term "Ground Zero mosque" and believes American Muslims are a threat to national security.

Donald Trump even cited Gaffney's work when he proposed his infamous Muslim immigration ban.

Cruz's list of foreign policy advisers, set to be released today, includes Gaffney as well as three people who work for his think tank, the Center for Security Policy, Bloomberg View's Eli Lake reported Thursday.

Lake portrays this as a "big tent" approach: Cruz is consulting both extreme anti-Muslim activists and national security thinkers who don't believe a world religion is an inherent threat to America. But Gaffney's views, and those advanced by his think tank, are paranoid conspiracy theories that are either exaggerations or outright falsehoods:

Gaffney's main argument is that Muslims are trying to impose Sharia, Islamic religious law, on America. This is not happening. "There is simply no evidence that US judges are encountering Sharia law, becoming enraptured with it, and tossing out their statute books," Amanda Taub wrote for Vox in 2014. But the argument has led to unnecessary, unconstitutional, and discriminatory bans on Sharia in seven states.

Gaffney argues that the Muslim Brotherhood has infiltrated the federal government and has called for a new version of the House Un-American Activities Committee, the inquisition into communism in the 1950s, to examine and "root out" its activities.

Gaffney said in 2009 that Obama "not only identifies with Muslims, but actually may still be one himself."

Gaffney was key to the conspiracy theory that Huma Abedin, an aide to Hillary Clinton who worked closely with the then-secretary of state, was connected to the Muslim Brotherhood.

These positions used to be considered fringe even within the Republican Party. George W. Bush famously reached out to American Muslims. Mitt Romney said in 2012 that "creeping Shariah" — the idea, spread by Gaffney, that Islamic religious law would make its way into American courts and threaten democracy — was "never going to happen."

But Cruz is considered the Republican Party's last best hope to stop Trump. And his foreign policy includes taking advice from the same conspiracy theorist whose ideas underpin Trump's infamous Muslim ban.

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