President Trump promised Monday to take aggressive action to curb the number of undocumented migrants in the US, and one of the bigger initiatives revolves around what's known as birthright citizenship. Trump aims to end the practice of bestowing citizenship on babies born on American soil to undocumented residents, which advocates say is guaranteed by the 14th Amendment, reports Politico. However, Trump's executive order is expected to face immediate legal challenges, notes the Washington Post, and it was unclear how quickly any such reversal could take effect.