US Constitution: Article I Section 9

“No Title of Nobility shall be granted by the United States: And no Person holding any Office of Profit or Trust under them, shall, without the Consent of the Congress, accept of any present, Emolument, Office, or Title, of any kind whatever, from any King, Prince, or foreign State.”

Nations whose citizens have committed terrorism against the United States in modern times:
Egypt, United Arab Emirates, Saudi Arabia, Lebanon

Nations targeted by Trump’s ban:
Syria, Iran, Iraq, Yemen, Sudan, Somalia, Libya

Nations with whom Trump has business interests:

Saudi Arabia, Egypt, Lebanon, United Arab Emirates, Turkey, Azerbaijan, Indonesia, Dubai, Abu Dhabi, Qatar

And a quick bit of history. Nations whose governments have been toppled / destabilized with US interference / assistance:

Korea (1945), Syria (1949), Iran (1953), Guatemala (1954), Congo (1960), Dominican Republic (1961), South Vietnam (1963), Brazil (1964), Chile (1973), Afghanistan (1979-1989), Nicaragua (1981-1989), Panama (1989), Haiti (1991), Somalia (1993), Iraq (1994-1996), Afghanistan (2001), Iraq (2003), Haiti (2004), Somalia (2007), Syria (2005-2015), Lybia (2011)

‘Those who cannot remember the past are condemned to repeat it.’
– George Santayana