Kaiser Henry: Of course, Rome's walls may be upgraded.

In fact, given the unpredictability of when such upgrades are possible, I would suggest the Chancellor have the discretion to insert them into the build queue as he sees fit without asking for governors' authorisation. I may propose this along with any other "housekeeping" revisions in a Charter Amendment. (Governors could always have the right to state in advance they do not authorise wall upgrades - but the presumption should be that they are allowed.)