Rate the following essay on its writing, argument, and language skills:
Google's driverless cars have driven more than half a million miles without a crash. With something this innovative and exciting there are going to be people who question the safety. There are always going to be those people who try to find every thing that can go wrong, it may seem unfair but it is necessary for our safety. Driverless cars are the future.

Safety? Everyone wants to know how safe they are and how reliable they are. Many people have developed semi-driverless cars. In fact Google "has had cars that could drive independently under specific conditons since 2009". The key words are "specific conditions". No one has developed a car that is fully driverless. That may be a good thing. Cars are machines, machines malfunction.

Google has modified a Toyota Prius to be semi-driverless equipped with "position-estimating sensors on the left rear wheel, a rotating sensor on the roof, a video camera mounted near the rearview mirror, four automotive radar sensors, a GPS receiver, and an inertial motion sensor". It seems very prepared for whatever could happen.

The cars that have been developed still need a driver. What's the point of having a driverless car, when you still need a driver? Some people who don't fully trust the concept, like me, need some control. That's why some manufacturers are "bringing in-car entertainment and information systems that use heads-up displays" to alert the driver when he/she needs to take over. Many manufacturers have developed an alert system, GM "has developed driver's seats that vibrate when the vehicle is in danger of backing into an object". Some others include a simple announcement and flashing lights.

The law has also made it hard to develope these driverless cars. What would happen if someone was to wreck in a driverless car? Would it be the driver's fault or the car's? No one has worked out the details yet. Most states don't even let you test driverless cars. The "traffic laws are written with the assumption that the only safe car has a human driverin control at all times". Once they prove that the cars are more "reliably safe" the other states will join in testing driverless cars.

It won't happen for awhile but driverless cars are our future. They have developed the necessary things to keep us safe and keep the car aware. There are still some kinks to work out, like the law. But many car manufacturers like Tesla, Mercedes-Benz, Audi, and Nissan have planned to release semi or fully driverless cars in the future.

Score: 4