You can still control a vehicle if the power steering gives out. If the steering wheel separates from the steering column, though, you'll have a much harder time.
Ford has issued a recall for 1.3 million vehicles in the US, Canada and Mexico. The recall is split between the 2014-2018 Ford Fusion and the 2014-2018 Lincoln MKZ. It covers Fusions built at both the Flat Rock and Hermosillo assembly plants, while every affected MKZ was built in Hermosillo.
The problem stems from the bolts responsible for holding the steering wheel to the steering column. They may not maintain torque over time, which means the bolt could loosen. If it's not secured, the bolt could back out and the steering wheel could separate from the steering column.
Obviously, that presents a massive safety risk, because a vehicle that cannot be steered is way more likely to end up in a collision.
The fix is pretty straightforward. Dealerships will replace the bolt in question with a revised unit that is longer and has "more robust thread engagement," as Ford puts it. It also has a larger nylon patch that should help it stay in place. As with other recalls, this will not cost you a dime. Ford will send recall notifications to affected owners via first-class mail in the near future.