Yesterday (January 27), President Donald Trump signed an executive order that would ban immigration from seven predominantly Muslim countries (Iraq, Syria, Iran, Sudan, Libya, Somalia or Yemen). In addition, the order will halt the U.S. Refugee Admissions Program for the next 120 days. According to CNN, while signing the executive order, Trump said, "I am establishing new vetting measures to keep radical Islamic terrorists out of the United States of America. We don't want them here."

During the 2016 presidential campaign, Trump spoke of a total Muslim ban. On December 7, 2015, the Trump/Pence campaign website released a statement that read, "Donald J. Trump is calling for a total and complete shutdown of Muslims entering the United States until our country's representatives can figure out what is going on." The statement went on to say that there is a "great hatred towards Americans" from a "large segment of the Muslim population." (This is not true.)

Incidentally, one day after Trump released that statement, Vice President Mike Pence took to Twitter to disavow Trump's call for a Muslim ban. Pence tweeted, "Calls to ban Muslims from entering the U.S. are offensive and unconstitutional."

His tweet is still available today, and with Trump's latest executive orders on immigration, people are quick to remind Pence of his former beliefs.

For the record, many believe that Trump's order that would target Muslims for "extreme vetting" is unconstitutional. The ACLU released a statement yesterday explaining, "Identifying specific countries with Muslim majorities and carving out exceptions for minority religions flies in the face of the constitutional principle that bans the government from either favoring or discriminating against particular religions. Any effort to discriminate against Muslims and favor other religions runs afoul of the First Amendment."

However, others have noted that there are laws that work in Trump's favor. As Sarah Harvard at Mic points out, the 1952 Immigration and Nationality Act says that the president can ban "any aliens or any class of aliens," as long as he can prove that they are a threat to the United States. Harvard also notes that challenging Trump's executive order on the basis of religious discrimination might be difficult to prove.

That said, this latest executive order from Trump is not being taken lightly – and there are ways to challenge it. The same day that the president signed this decree, The Council on American-Islamic Relations (CAIR) began to take the necessary measures to file a lawsuit in response. According to CAIR's litigation director, the lawsuit will "challenge the constitutionality of the order which very clearly is designed to target Muslims."

Related: President Trump Says ‘Persecuted Christians’ Will Be Given Priority Status as Refugees

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