If further terrorist attacks occur, this is proof the PA should be kept and more laws are needed.
If no terrorist attacks occur, this is proof the PA is doing a good job, and should be renewed.
After 50 or so years of that, most living people will not remember a time when there was no PA, and repealing it will be as unrealistic as repealing the income tax today.
PA's expiration date was nothing but a smoke and mirrors show designed to placate those who didn't like the PA but could stomach it for a limited time. Its sponsors knew it would be permanent.
It's painfully obvious, to all but the most naive.