"Understanding the reason behind the attacks" was easier said than done.
One should know that the top secret information they got must had been thoroughly researched and investigated by the US government. Hundreds of experts in this field had made a thorough and comprehensive study from every angle. There were no loopholes in the study. And yet, even they could not find the reason.
Sheyan believed that even an idiot could tell the danger posed by this kind of killing machine that could change into any form and possessed an exceptionally smart AI. Surely the US government was willing to pay any price to find out their secret.
To find out the secret that the US government could not uncover with its utmost effort was a hard ask of anyone. The only advantage Sheyan had was that he was very familiar with the history of the Terminator World. He might know some information that the people in this world, in this era, did not. Maybe that would help.