If the Pentagon was going to partner with Google to develop drones, maybe it means the talented people required to develop such tech simply don't want to work in the military field, but they exist elsewhere working on others projects. Money can solve all the material problems, but if people still don't want to work toward autonomous jet fighters or killing machines, then it can explains why it doesn't exist at all.

What about using those 1.4 trillions dollars to support R&D, businesses and help people to live longer and have a good life?

What about investing 1.4 trillions in genome research? in cancer research? in renewable and nuclear energy production?

Sorry, but I prefer to be a naive software developer helping connecting people together around the world than someone who helps random people to get kill.

We are not in the cold war anymore, people don't communicate with papers. We can solve problems by other means than sending missiles to each others, we can see beyond the military propaganda of the countries. We know when something is possible but not preferable : killing drones are one of those project. Technically feasible, ethically not acceptable.