Which was unforgivable - so why would you equate them? Or are you just saying the equivalence is only in being a special case?
I'm making an assumption, based on the text of Mark 3:28-30, as well as the similar Matt 12 passage, that there is only one unforgivable sin. Maybe that's a bad assumption, but think about it for a minute.
What was the Holy Spirit's role toward the pharisees Jesus was condemning? The visible means was the miracles Jesus was doing, and the purpose of those miracles was to reveal who Jesus was. For what purpose? Salvation.
Instead, the scribes and pharisees gave the glory belonging to God to demons instead, which was rejecting the truth the Holy Spirit was trying to convey to them--that Jesus Christ is lord over even the demons, and He should have been recognized as lord of the pharisees as well.
What is unbelief? It is rejecting Jesus as lord--not believing that He is who He said he is. Since the Holy Spirit convicts the world of sin (John 16:8). If the purpose of convicting the world of sin is to draw them to Jesus, and those being drawn do not believe, then they commit the unforgivable sin--unbelief in Jesus at the conviction of the Holy Spirit.
I think they are one and the same sin.
How does that work with unbelief, you might ask, since most of us have spent some time in unbelief? The pharisees also spent some time in unbelief, but they still had the opportunity, even after Jesus' death, to believe, and I think many did (you can tell because of the "men from James" passage (Gal 2:12) and Paul's constant struggle against those who wanted to impose the Mosaic law on the Gentiles). Thus, the unbelief spoken of is more of a lifelong rejection, or a rejection so strong that at some point God gives up on them and allows their depraved minds to go full bore.
Not necessarily related, but doesn't it seem like these school and church shootings are by people who have kind of gone off their rocker, and there is no longer anything that holds them back from the evil in their hearts?
And, doesn't it seem like the more our society turns its back on the truths of scripture and the influence of God, the more of these shootings there are?