In a democracy, all people are equal. There can be theocratic monarchies and dictatorships but there cannot be a theocratic democracy in which some people claim superiority over others.
Secularism is thus integral to democracy.
Theocratic democracies often get subjugated by the military and the clergy. They need to review their practices. The concept of secularism as it evolved in the West is of separation of the state from the church. It is being globally promoted. The tradition of secularism as it evolved in the East is different and needs attention.