[GunRunner]

Basically, they were warning against Earth attacking other worlds.

I guess so. But I have to question the wisdom of Klaatu's civilization:

For our policemen we created a race of robots. Their function is to patrol the planets in spaceships like this one and preserve the peace. In matters of aggression we have given them absolute power over us. This power cannot be revoked.

Nothing makes me feel safer than having a race of unaccountable, super-intelligent, indestructible robots in charge.

I hope someone performed some QA tests on their programming. What exactly do they do if one of these things goes haywire?

[dbz77]

I hope someone performed some QA tests on their programming. What exactly do they do if one of these things goes haywire?

See Terminator 3: Rise of the Machines to find out.