In the rush to do something about terrorists, mistakes are going to be made.

What should concern Americans is some of those errors will make life more difficult for law-abiding people while accomplishing little, if anything, to prevent massacres.

It is being suggested by both some Republicans and some Democrats in Congress that gun sales to people on the government’s terror watch list should be restricted. If not banned entirely, they should be subject to a 72-hour waiting period, it is suggested. During that time, the authorities could attempt to convince judges firearms should not be sold to specific individuals considered risks for terrorist activity.

Those compiling terror and “no-fly” watch lists have made many errors. For example, parents of young children have been told their sons or daughters could not board commercial aircraft – because their names were on no-fly lists.

On several occasions, the late Sen. Ted Kennedy, D-Mass., was delayed in boarding airplanes – because the name “Kennedy” had been used by some shady characters.

Meanwhile, many very real threats are not on such lists.

Better efforts to prevent terrorist attacks are needed. But they need to be effective, rather than merely easy.