What If Our Robot Overlords Are 50 Feet Tall?

I remember a Fifties SciFi movie from my youth about a 50 Foot woman. She terrorized the countryside just by walking around. As a male reaching puberty, I was far more interested in other parts of her anatomy; but, still, now we can build 50 foot robots that move and walk. How far away are we from wars fought completely by robots? While we are all in our houses, cowering in fear over a pandemic, the robots are going to be out tearing up the forests and trees. Give them AI semi consciousness. What could go wrong?