The Legality of Enforcing Deportation

Enforcement of deportation of illegal aliens–particularly those who came here as adults and or committed crimes in our country –is legal and doesn’t violate due process because they are not citizens or legal nationals of this country and by our laws, entering our country as an undocumented migrant is illegal. As I understand it, the right of due process is a privilege that only applies to citizens and a sovereign nation has the right to secure its borders and enforce its immigration laws. Many other countries do this. Why can’t we do that as well?