Is it intentionally ending the life of a human being? Well, what life, what is a human being?
It's intentionally terminating a pregnancy? Yes. Is that bad? Well, if the would-be-mother doesn't want it it's definitely bad, and if the would-be-mother wants it then it definitely seems cruel to not do it, but when society tries to impose whatever morals on these people the arguments start to look very silly very soon.
The main argument against abortion is a strange begging the question fallacy mixed with consequentialism: if the abortion would not happen then things would go great and a human would born (the implied assumption is that it's somehow unquestionably good).
I fundamentally disagree. You objectively cannot “kill” something that is not “alive”. That is just a fact of life itself. A government can legislate all they want, but it does not make an unborn fetus any more alive. And thus any law rooted in this idea is fundamentally absurd, preposterous, and so downright stupid that on the principle alone (aside from the many others) any such ban shouldn’t be followed.
To entertain the idea that government can legislate whatever it wants is to imply that a government can dictate the laws of physics. It’s just nonsensical.
The fetus is alive. It's a bunch of cells. There's a causal interaction to remove it from the host which makes it a bunch of dead cells.
Legislatig physics is stupid, but what if some state said by law which interpretation of quantum mechanics is the correct one? Stupid, but not much different than building codes. Or say that prions are alive and can run for office... stupid, but there used to be a lot of absurd laws. (If someone works on Saturday they shall be put to death. Sure, what's work? And then there are many many many interpretations of what's work.)
Because it's not murder. Legislating that it is does not make it so. Full stop. That's like a government trying to legislate that the sky must always be blue, or that it's illegal to frown, or that 2+2=5. Just because it's a law does not make it just or sensible, and I would hope that in modern society we would not blindly obey unjust/unnecessary/unwelcome laws without questioning.