Loan was a staunch South Vietnamese nationalist, refusing to give Americans special treatment in his jurisdiction. For example, he rejected the arrest of a Vietnamese mayor by American military police and insisted that only South Vietnamese authorities could arrest and detain South Vietnamese citizens. He also insisted that U.S. civilians, including journalists, fell under South Vietnamese jurisdiction while in Saigon. Loan's uncompromising stand caused him to be regarded as a troublemaker by the Presidency of Lyndon B. Johnson. Loan was also skeptical of the U.S. CIA-backed Phoenix Program to attack and neutralize the clandestine Việt Cộng infrastructure.