Bitcoin by contrast is like a rotten borough where all the votes are bought: you get a vote in bitcoin in exact proportion to how much of the mining capacity you own.

But that those currencies issued by dictatorships having value as you say, doesn't really have much to do with bitcoin, apart from being another example of currency.

Those dictatorial governments have real world clout, they can make things happen, by contrast bitcoin's govt is it's users, and as a group the only changes they can affect on the real world are changes directly pertaining to bitcoin.

Also, those currencies issued by dictatorships, for the most part have zones where they are 'the coin of the realm,' meaning they are the only or one of the few currencies widely circulated. This gives a currency value.

A currency's value derives from some combination of it's supply and it's currency(this use of 'currency,' meaning how widely it is accepted as payment for goods, services, etc.)

So there is a lot of value in the US dollar system for example, because it is a currency that is used widely throughout the world.

http://money.cnn.com/data/commodities/

The reason I think it matters is that when commodities are used as currencies (e.g., gold, silver), the use value supports the currency value. If gold's value as a currency falls to zero, you can still make some nice jewelery. Whereas if people stop accepting dollars or Bitcoins for things you actually want, then they are basically useless.