In the years that follow, Annorax is assimilated by the Borg.
So Anwar, when Chakotay tried to remove that asteroid, every one would forget that asteroids existed?
It's a chain root of effect and cause.
After "X" is removed by the weapon, the entire universe rushes to compensate for "X's" absence. the weapon is only responsible for the first domino, and after that they can only predict what happens to the rest of the dominoes, and not that well.