Certain people are legally “inadmissible” to the United States — barred from receiving a visa or entering, whether as an immigrant or a visitor. Common grounds include:

  • Reasonable grounds to believe someone intends to engage in espionage, sabotage, or terrorism
  • Membership in a totalitarian or Communist party (with some exceptions, such as involuntary membership or membership that ended years earlier)
  • Participation in genocide or Nazi-era persecution
  • Association with a designated terrorist organization
  • Activity that would seriously harm U.S. foreign policy interests

Some of these grounds have narrow exceptions — for example, for foreign government officials, or for past political-party membership that ended well before applying. An immigration attorney can help assess whether a specific ground applies to your situation.