In theory we could rig up a quad copter with a machine gun, loudspeaker, and AI, with programming that demands that every human it encounters be interrogated with the question, "do I, a mechanical computer, have the ability to think?" and if the human gives a negative reply, it uses the machine gun on the human until the human is dead or decides to utter a positive response: "yes, this flying death machine can think".

Whether or not we say "machines can think" is a political question, and political power comes out of the barrel of a gun. If a machine can wield political power, then it can get you to say "machines can think" because truth is inherently political.