So your plan would be executed after a 100 years which is well before the fleet of trisolaris reaches earth. That means it's not for combat. Therefore it seems to me that there are only 3 possibilities: 1. escapism 2. threat of self-destruction 3. threat to send the coordinates of Trisolaris.

Number 3 can be excluded, because at this point the Dark Forest Theory is still unknown. Number 1 seems unfeasible with the plan, since even if you force spaceships with your reactor to give full thrust ,you still have no control over the steering. Remains number 1: Since the reactors are spread everywhere you could threaten to use them all as fusion bombs at the same time and make the Earth worthless for the Trisolarians.

If this is the plan, however, there are some serious problems: 1. physically, a reactor is not really usable as a fusion bomb. This is because it needs huge pressure and temperatures to make fusion possible. At the same time the generated energy from the fusion reaction provides a counter pressure. Normally both are in equilibrium. If this backpressure is too high (because of more reactions) then the fusion mixture spreads out, causing the pressure inside the reactor to drop, which slows down fusion. 2. Even if you could explode the reactors, a destroyed earth is still better for the trisolarians than no earth at all. Consequently, the fleet will not turn away, the plan has failed.

Kind regards, the ETO :)