Hi MBargo,
Recently we finally set up the tools to "cancel build job" and "downgrade/remove tile". The latter is a job similar to building, where an ant will come to clear out the tile (dropping 50% of its value in food in the process).
The bottom line is that it should be possible for enemies to use the same rules to destroy tiles which would be really cool. It is something that won't come up in the imminent release, but if we have most of the framework for it already, I would like to experiment with it in the future.