So... Mandir is literally god%u2019s palace; it is built according to shastric specifications, and once the images are consecrated it means the gods have accepted the invitation to reside in the respective temples. This is what gave temples their power and sanctity in all ancient traditions.
Temple entry cannot be a secular right of non-believers. It is a privilege of the believer, and that is why truly reform-minded Hindus in previous centuries fought for the right of underprivileged believers. like Harijans (Dalits), to enter temples. This is an issue to which Hindu society urgently needs to rededicate itself.