If you want to conquer the tongue, then you fix up your mind that you shall not take anything which is not offered to Kṛṣṇa. Then your tongue will be controlled. Tāra madhye jihvā ati lobhamaya sudurmati. Tongue is the bitterest enemy of the living being. The tongue is dragging. Jihvā. "Kindly give me this immediately. Kindly give me this wine immediately. Kindly give me this tea immediately. Kindly give me this cigarette immediately. Kindly give me this meat." Why? Control. Kṛṣṇa says, patraṁ puṣpaṁ phalaṁ toyaṁ (BG 9.26). So we have to take prasādam, eat Kṛṣṇa prasādam. Then naturally the other things will be negativated. This is the position. Suhṛdaṁ sarva-bhūtānām (BG 5.29).
So if all human beings become vegetarian, not vegetarian, but eater of the Kṛṣṇa's prasādam, all these liquor house and slaughterhouse and brothels will be closed. This is Kṛṣṇa consciousness movement.