There are great pieces all around by George Will (WaPo), James Taranto (WSJ), and Jonah Goldberg (LA Times), but to take a simpleton's stab at the issue:
Government unions, of which over 36% of government employees are a part, and which were actually illegal until JFK allowed them by executive order in 1962, should not be allowed to exist. Perhaps the simplest reason is because there is no reason for them to exist; are we that concerned about government taking advantage of its own workers, of placing them in harm's way or giving them unfair working conditions? Quite simply, no.
But the more important and clear reason today is that such unions exist almost completely to protect its own at the expense of government... and therefore, taxpayers. Government workers have a vested interest in increasing the size of government - whether it makes sense or not for the people whom they serve - to protect their own jobs and benefits. Government exists to serve the people, and allowing the existence of a group whose primary motivation is to serve itself over the people they are meant to serve is tantamount to organized suicide.
The best analogy is to imagine running a business, and knowing that you must retain a specific staff member to handle your HR - and you are not in a position to hire anybody else, only this specific individual. However, you are not allowed to dictate terms; rather, this staff member will dictate to you what the terms of her hire will be. In fact, despite your being completely open with this staff member that you cannot afford to meet her demands, she is demanding compensation completely out of line with the industry standard, and has rallied friends of hers from related departments to tell you to meet her demands. You've countered with a proposal that is extremely generous, backed clearly by the shareholders of the company, and yet all you hear are more cries that what you're offering is a slap in the face to this HR staffer, despite her having been grossly overcompensated for decades. On top of that, a board vote would overrule her demands, but a few board members left to avoid allowing a quorum to have a vote on the matter.
The obvious question is not merely how to solve the riddle; instead, it is the following: Who in their right mind believes such a company can successfully function; and, once you've determined the answer to that, then why the heck are we running our governments this way?