No, they didn't hire Hamas. They actually created them like they exist today.

By not doing anything after the Oslo agreements and just sitting their happily that they could de facto occopy the area while someone else (the internation community) pays until Hamas got a majority in 2006.

By even then not supporting the peaceful side against Hamas but sitting their gloating as Palestinians killed Palestinians.

By indirectly supporting Hamas to use them as an excuse showing that the National Authority isn't speaking for Palestinians and so there is no need to work with them in any way.