Why it is absolutely necessary to protect mosques from politicians

On theory I agree. There is no problem with mosque serving as non-political non-discriminatory role in social sphere.

However the real experience shows that very few mosques have been able to retain their MAIN purpose aka spiritual enlightenment of their congregations. The rest have become a circus for politicians and Mullah-looking-politicians.

That reality is the one that prompted the thought about purifying and refocusing the role of mosque away from the dirty business of politics.