How to pronounce “diachronic” in English

There and then, I am part of the Department of Diachronic Operations, a black budget arm of the United States government that has gone rather badly off the rails

The Fuggers, above all people in this world, understand the dangers of diachronic shear.

But you already knew that, because when I'm done writing this thing, which for reasons that will soon become clear I'm calling diachronical, I'm going