unlock directory and all of its children

I am trying to remove a directory with many children. When I do, I get the message "The operation can't be completed because some items had to be skipped. For each item, choose File > Get Information, make sure "Locked" is deselected, and ...

I have unlocked the parent of this complicated collection. There are thousands of individual files within it, in a complex directory structure. Hunting down each thing that is making a problem is time consuming and tedious. Is there not a way to propagate unlocking throughout the directory structure?