Laws vary by locale. If it became community property then its destruction was illegal, and then there are normal legal channels for the community to go through to get recompense. In some communities you can’t put various things in that area and it might have been technically illegal from the word go. But the local council could change that and put a new one up.
What is really distressing is to see all this implied “Arrrrrgh, this Islamist is keeping us from worshiping the Lord.” Er, not so fast. In fact, if visiting that cross substituted for observing the Lord performing the work of the cross in their lives, maybe God did them a favor by removing an obstacle... context, context, context.
No graven images...............it’s one of the top 10............