Don't attack the stones. Find out exactly who funded it and had it put up. If you can't find them, then find the company which did the construction and make someone there talk. Then eliminate the people who funded and had it put up. And if something similar gets put up again, pushing for the mass elimination of the human population, eliminate the people who did that. And so on. This is how change is made. Remove the people with the bad ideas. You can't kill ideas, for sure, but you can sure as hell limit their proliferation.