Some assumptions we have to clarify:

• Is it in the best interest of a mining pool or conglomerate to have 51% of the hashing power? (Y/N)
• Are threats such as deliberately mining blocks with zero transactions a legitimate concern? (Y/N)
• Do miners have majority control over which blocks are considered valid? (Y/N)
• Are people in general altruistic, being ok with seeing their wealth diminish if it goes to "the greater good," if allowed to make that choice in private without coersion? (Y/N)
• Are people stupid apathetic sheep who don't care about what happens as long as it doesn't affect them directly?(Y/N)

I would suspect your answers are Y, Y, Y, and maybe Y and Y. If that is true, I would say you may be wrong on the first one (read my sig), definitely wrong on the second one, and mostly wrong on the third. Fourth and fifth are a tossup, and fifth may be a major issue, depending on how things pan out. Specifically whether a drastic decrease in social services will force people to start caring and being more responsible. Also, as is the point of my sig, just as P2P file sharing is forcing people to rethink intellectual property, threat of 51% attacks may force people to rethink democracy and majority control. If that happens, the first thing will become a big N, as will the idea of "democracy" and minarchy.

But, these are really assumptions that neither of us can answer concretely (except for the second one, which is trivially easy to fix), so...