Why destroy Laketown's bridge?

[Rikae]

Originally Posted by Sauron the White

Okay. These assumptions may be accepted by many here and that is fine. I just cannot in good use of my faculties accept them.

Maybe I simply do not have the faith.

Leaving aside the inaccuracy of several of your characterizations of the assumptions of other posters here...
You yourself seem to be basing your opinions on an assumption I find strange indeed - that Tolkien mentioned the destruction of the bridges not once, but twice, without having any reason for doing so.