The biblical account of Jericho involves the righteous laying siege on a walled city. The walls were knocked down at the blowing of a ram's horn (sometimes referred to as a trumpet). Rufus uses this story as an analogy -- here, the religious right (who refuse to ever compromise or better themselves, in his eyes) are in their walled city and he is the one laying siege. They are hard and heartless, but he is saying he can be too, and if the blowing of the trumpet doesn't do the trick, he's willing to go to more extreme measures (i.e. using a cannon).
The biblical account of Jericho involves the righteous laying siege on a walled city. The walls were knocked down at the blowing of a ram's horn (sometimes referred to as a trumpet). Rufus uses this story as an analogy -- here, the religious right (who refuse to ever compromise or better themselves, in his eyes) are in their walled city and he is the one laying siege. They are hard and heartless, but he is saying he can be too, and if the blowing of the trumpet doesn't do the trick, he's willing to go to more extreme measures (i.e. using a cannon).