In the 1970s, when word got out that the federal government was spying on its own citizens, there was such an outcry that Congress severely restricted the practice, and the agency involved virtually stopped doing it altogether. Congress made the right call then by passing the Foreign Intelligence Surveillance Act. Now, Congress should move quickly to curtail a renewal of the practice, which is being done this time in the name of fighting terrorists.

A carefully detailed report last week in The New York Times described how President Bush, in the wake of the Sept. 11 attacks, authorized the National Security Agency to eavesdrop on Americans without getting search warrants. Officials familiar with the operation say it has resulted in uncovering a plot to blowtorch the Brooklyn Bridge and another plot to detonate fertilizer bombs in British pubs and train stations. Meantime, the NSA actively spies on about 500 people and has eavesdropped on thousands of others, resulting in almost no criminal charges.

In addition to being an invasion of privacy and a misuse of the NSA, the practice isn't necessary at all. The court responsible for reviewing NSA requests, the Foreign Intelligence Surveillance Court, in the past had routinely approved them. Bypassing the court, however, allows the government to conduct possibly unlawful and unconstitutional operations against U.S. citizens.

After some national-security officials criticized the monitoring, parts of the program were suspended or revamped last year. Nevertheless, the program should be dismantled. Terrorists can be caught and punished without sacrificing the privacy rights of ordinary citizens.