His state of mind also plays into his action as he just saw Genosha massacred by a bunch of sentinels. I dont think his actions were self defense but...
TBF the only telepaths we've seen her interact with were Maddie, who didn't like reading people's minds if they didn't present an immediate threat or...
From last episode it seemed like the prime sentinels would be like TWD zombies, activated upon death but as we got the backstory the programmig can ...