According to the book, goldstein states the reason for the constant realignment between the superstates. what is the reason

The correct answer is, Golden states that the reason from the constant realignment between the superstates was the following.

What the character Emmanuel Goldstein says is that superstates have the risk to disappear if they attack another super state. This means that super states can defeat another super state, but the damage is for both sides.  

Emmanuel Goldstein is the character in the fictional novel “1984”, written by Orson Wells. It was published in 1949. In the novel, Emmanuel Goldstein writes the “Theory and Practice of Oligarchical Collectivism”, an important part of the novel.

after the senate and the house passed different bills and deadlock threatened, a compromise bill was worked out with the following provisions: (1) missouri was admitted as a slave state and maine (formerly part of massachusetts).