http://www.npr.org/2015/03/02/390245038/ben-franklins-famous...
However, I think it has taken on new life and new meaning and is cautionary in terms of "be careful what you are giving up...". 9/11 attacks were successful in their goals based on exploiting the FAA guidelines for hijackers, not because we didn't spy on these people. No one imagined them turning a plane into a bomb. I think non one believes that if hijackers tried to take over a plane with box cutters today that they wouldn't be subdued or killed within minutes.
It's also old-fashioned. It reminds me of something Trump would say.
In a modern democracy everyone deserves safety and security, even people who believe the government ought to be granted additional power to constrain "essential liberty" in certain situations or within certain more expansive limits. They may eventually be proven unwise or evil policy choices, but the people advocating them still deserve safety and security -- precisely because they live in a democracy.
Remember, they have not stopped any terrorist attacks in the US with all the new surveillance since 9/11 (to my knowledge).
"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety." -Ben Franklin