Google also has employees in different countries.

Would you be okay if your AI works as American ends up in the hands of the Russian military?

Why should a German, or French, or Russian Google employee then accept that their work ends up in the hands of the US military?

EDIT: Yes, they won’t directly work on the drone program – but the drone program will more likely than not be reusing ML technology built all across Google, and everyone that worked on that now knows they are personally helping the US military-industrial complex.