Couldn't sunlight concentrated with mirrors be used to desalinate water in the middle east cheaply?

By distilling it without using electricity or any other power source other then the sun. Could this be used to harvest the salt left over from the process as well? Would this work in any bright hot sunny area close enough to the ocean to pipe sea water to it? Wouldn't building enough of these generate enough water be able to turn the deserts of the middle east into gardens and fields bringing prosperiety to the people there and produce enough fresh clean water and food to end world thirst, hunger and help end world poverty? Wouldn't this also work well for Austrailia especially considering the once in a thousend years level drought they've been stuck in and help end terrorism at the same time because it would end those root causes that lead to it?