Just so more people know, the old fashioned hack saw will work in many cases. It does less damage.
A flat blade screw driver and a hammer may have worked to spin the flat part around too. Just tap, tap, tap and around it goes.
Also, no Tape on those sink connections. Water supplies come "with" rubber cone washers. All the tape does is get between that seal, and make the threads harder to run down and make tight.
I know the flunky at the home center likes to sell tape, but it's almost never, ever needed.
A big part of my job is taking everything apart, removing all the tape and putting it back together clean.