It is amazing to read many of these responses because they show, what I believe, is an unrealistic understanding of what a full self driving system will be capable of doing.
In terms of aircraft, small to medium size planes avoid flying in extreme weather with or without autopilot systems. Drivers should do the same. It is ridiculous to believe that full driving is going to allow you to drive thru a blizzard or hurricane. Sensible drivers know to stay off the roads in such conditions. But what about 'normal' driving conditions. Humans have trouble navigating day to day driving conditions as it is. An affordable FSD system cannot be expected to do that much better than a human. It is a fantasy to believe otherwise. Under present road conditions and distracted drivers, such capability would require onboard super computers, a suite of sensors that are unaffordable and unattractive and even then would result in jerky, slow driving responses to a busy commuter route.
Under near perfect conditions, with well marked roadways, intersections and other obvious obstacles, full self driving using Tesla's vision system could successfully navigate without driver input. But such a world does not, nor will it ever exist in a free society.
To answer the original question posed in this post, if we are realistic about our expectations for the definition of full self driving than I believe in ideal driving conditions it is already possible. The question becomes when will the obstacles to FSD be removed to allow it to work reliably.
Think about what Tesla has already publicly disclosed and accomplished at a beta level, sign and signal recognition, vehicle and pedestrian identification, obstacle i.d., navigation to a destinations, autopark, traffic awareness, self steering and braking and growing AI data based to side in split second decision making. Did I miss anything? IMHO