It seems that you struggle to understand what decentralized means.
If a bank, an institute, an organization, a country of even me issue money then that's not a decentralized economy. Bitcoins are issued by themself. There is absolutely noone issuing them. If you can't see how revolutionary is that then i guess it can't be helped anyway.
If nobody mines bitcoins, there will be none, period. I'm not going to get into a petty argument about what decentralization means (actually you're catching at every possibility to confuse issues). Decentralization, whatever you may next mean by it, won't make Bitcoin any better, since it doesn't prevent its accumulation. Go and see its present distribution between owners...