Immoral, all waste and needless destruction. Vandalism.

I think the question is too vague. What did that building ever do to you? Even if the church building burnt down to the ground then the people in the church will just go some where else until it is rebuilt. If you really want to "Burn down a church" then expose them for who they really are. If they are doing bad things then make it public, that would do more damage than setting a building on fire...

Wanton destruction is never desirable.

Immoral. People have a right to believe what they think is best for them to believe. A church is a place for freedom of religion and free expression. Why burn down a building when it is the idea that is objected to? Ideas are changed with better ideas.