One synonym for "loyal to regime" is "faithful to authority." Other options include "committed to governance," "devoted to the government," and "dedicated to the ruling power." These phrases convey a sense of unwavering support for those in charge, regardless of the specific policies or actions taken. Alternately, one might use "aligned with the ruling party," "supporting the establishment," or "in sync with the political system" to describe someone who is steadfastly behind their government. Regardless of the term used, the idea of being loyal to one's regime implies a willingness to defend their leaders and follow their directives without question.