Mamdani needs to publicly apologize to all of America. Mamdani needs to publicly voice his condemnation of violent Jihadi Terrorist Attacks and Bombings on American soil. And Mamdani needs to voice his decision to harshly punish the Jihadi Terrorists to the very fullest extent of the US Law.
If he refuses to do so he is thereby aiding, abetting, and incentivizing Terrorism and therefore must be removed from public Office, removed from the United States, and banned re-entry.