Presidents must be born on U.S. soil, or territory. If Cruz were president, that would open the door to every child fathered by military personnel, born to local women, who were stationed in a foreign land, for instance, Germany, Korea, Vietnam, Japan, etc. A president from a foreign land could be a national security risk with allegiance to their birth land; founders wrote "natural born, and citizens at the time of the writing of the Constitution," allowing for them born in England to hold public office. They purposely wrote an exemption for themselves, Cruz wants to rewrite the Constitution.