What's not to understand? Lots of churches flaunting it and the IRS doesn't go after them because they know its not constitutional and would very very likely be overturned.

My point is that if churches would stop being cowards they could get the Johnson Amendment overturned. Then they could keep their tax exempt status and speak about political issues freely.

I agree with you that pastors shouldn't censor themselves because of tax exempt status, however from the pastors I've talked with they don't mention tax exempt status. They say they don't talk about politics because they think it's unbiblical. They cite 1 Peter 2 about being exiles in a foreign land, or 1 cor 5 about not judging those outside the church. I was visiting a friend's church a few weeks ago and the pastor preached from 1 Peter 2 and flat out said "we're not of this world and we disobey God when we involve ourselves in the matters of this world" or something to that effect, and that the only thing we're to do is "preach the gospel".

Obviously that makes no sense and doesn't even remotely fit in the context of what is being talked about in 1 Peter, but what can you say to a pastor that has been indoctrinated for 20 or 30+ years that God says no politics? Just like the saying the science advances one funeral at a time, the same is probably true for churches as well. Most pastors are probably never going to change. They're just going to retire and die off, and hopefully they are replaced by pastors who understand how important pastors and churches are to all aspects of society, including politics.