What do you do when a building is historical, but impractical?

New Focus on a Forlorn Cleveland Tower

I don't know the answer to this one. Marcel Breuer's 1971 Cleveland Trust Tower may be ugly. It may be poorly maintained. But that doesn't mean it should be torn down. Why do we prize 19th century architecture (and earlier) above all else? Well, that's obvious. Older architecture is simply prettier. There's nothing pretty about this building. But it is an important example of modern architecture. So do we just leave it there in all its impracticality? Do we try to adapt it to modern needs? Or do we just build something better? While I believe historic architecture should be preserved, I also think that buildings have a natural lifespan, and when a building's lifespan is coming to an end, it's better that it goes out in a blaze of explosive implosion and wrecking balls than falls into disrepair and crumbles slowly. Architecture needs to evolve constantly. New buildings have to be built somewhere, and it's better that they replace old buildings rather than encroach upon the natural environment. Think of it as a physician-assisted suicide plan for architecture. I'm just not convinced the Cleveland Trust Tower is a terminal patient yet.

I can't help but think this whole situation is somewhat ironic, though. In the 1950s to the '70s, many of the 19th century buildings we would now call architectural treasures were torn down in "urban renewal" programs and replaced with blocky, concrete creations like the one we see above. Now it's those very buildings that are danger. We finally realized our mistake from the first time around; will we be too late to realize it this time, too? Or is it simply time for us to switch off the life support machine on modern architecture?