Maybe a bit besides the point, but according to wiktionary, both are valid ways to describe a Slavic emperor...
Anyway, it's just incorrect name calling.
A female Tsar/Tzar/Czar is called a Tsarina/Tzarina/Czarina, not a Czar (I know, nitpicking), Czars were in fact absolute rulers, so there couldn't have been 30 or 31 of them.
There have been only 2 at the same time in history. One such period was when both Serbia and Bulgaria had a Tsar and another time was when both Bulgaria and Russia had a ruler commonly known as a Czar, although that's technically incorrect, since the official title of the Russian ruler by then was Imperator (although the title Czar was still used by most people). In one case the Czar co-ruled the empire with his brother (Peter the Great's case), but I don't know if he also bore the title Czar.
Since Tsar means Emperor, it'd mean that Obama has surrounded himself with 30 or 31 (depending on who you ask, I guess) Emperors. A bit of a silly notion, if you ask me.
http://en.wikipedia.org/wiki/Czar
But what could the idea behind this be? Why would they call these people Czars? The most important Czars & Czarinas have been
1.) Ivan the Terrible, whom is said to have had fits of rage and is said to have killed his own son, not something I'd say any of the 30 or 31 'czars' has probably done. He also created the Oprichniki, which was Russia's first secret police, which can no longer be done today in the USA, since the CIA already exists and he made an Empire out of a small country that had a hard time defending itself. Not something to be ashamed of, I think.
2.) Peter the Great, whom is best known for modernising Russia. I honestly doubt the anyone could be against that...
3.) Catherine the Great, who re-vitalized Russia during/after which became recognized as one of the great powers of Europe because of that.
4.) Nicholas the II, who was deposed by the bolsheviks & later murdered by them. I really hope the GOP or Beck or Hannity or anyone else would want to do that. They'd have to change their entire ideology before they even could.
Anyway, what I've tried to make clear is that it's just a term used by certain people to make other people look bad, without knowing that instead of making the people they want to look bad actually look bad, they are in fact making fools of themselves.
Since US media in the 40's, 50's, 60's, etc., often did their best to make anything coming from Russia look bad (it's probably also true to say that the Russian media did exactly the same thing) and since these people or their parents were raised during these times it's only logical to assume they actually believe that anything that has
ever come from Russia, even before the Russian revolution, is bad (this includes Czars).