Capital projects are the wrong thing to wait for
Public owners often frame hardening as one big build they cannot afford, so nothing moves. The workable version is smaller. Find the handful of places where an event would do the most harm, address those first, and fund the work out of maintenance over time rather than a single line item nobody will approve.
Retrofit that fits an occupied building
A courthouse or a school stays open while it is improved. Protection a crew can install in an occupied building, on an ordinary schedule, is what makes public hardening actually happen. The bar to aim for is set by the threat the building credibly faces, not a one-size checklist.
Phased or not, that means protection rated to the threat the building credibly faces.