Israel gets most of their water through desalinization plants. The countries on the Mediterranean Sea could build many desalinization plants and
irrigate the desert for farming. At one time, the area was very fertile, so it could be possible to return it to its former lush glory.
A reality is that actual desertification is happening in many places across the globe.
I do suppose that de-desertification could remedy the situation. However, I also feel that nature isn't a force to be battled. If it's going to turn
into a desert, it's going to. It's up to us to evolve to use that land more efficiently.
A lot of the desertification in Africa is caused by poor farming techniques. I personally hate goats because they cause a huge amount of destruction
to arable land - they don't crop like cows and sheep do, they literally pull plants out by the roots. They are also agile climbers and can be seen
standing on branches in trees munching away.
Where there are large herds of goats, you will also see how the vegetation has been decimated. Once the vegetation is gone, erosion begins to take
place, and once the top-soil has been removed, the land becomes a desert.