Are boycotts effective in “reclaiming our culture”?

Recently I was notified that there is an American Family Association boycott of Home Depot over their LBGT policy.

This morning, I was made aware of a boycott of Fort Worth public transportation because they agreed to display advertising from an atheistic group. The story can be seen by clicking on this link.

I question whether there is a Biblical basis for pursuing these boycotts. Do these efforts further our commission to make disciples? Do they generate more heat than light? What message does a boycott send to a the world at large?

If we have the Truth, do we have to respond in fear when lies are disseminated? Are we really confident that Truth wins in the end?

Your thoughts?