The attacks in London last weekend exposed in a matter of minutes just how vulnerable our free societies truly are. All it takes is a van or a knife and an unsuspecting bystander to turn a fun night out on the town into a horrific nightmare. Course, we shouldn't need any reminders, but let me give one yet again: We are at war with Islamic extremists. We have been for years, and, I'm sorry to say, there's no end in sight. It's easy to forget this as we go about our daily lives, but our enemies have not-and they will not. They've never taken their eyes off the ultimate target either: the United States.

Yes, we're at war with a vicious and unyielding foe. And just as our enemy can attack us with the simplest of everyday tools, the strongest shield we have in our defense is just as basic: It is the intelligence information of knowing who is talking to whom about what, where, when, and why. After the 9/11 attacks, our national-security agencies developed cutting-edge programs that allowed us to figure out what the bad guys were up to and stop them before they could perpetrate such heinous attacks. Very often the intelligence they've collected has made the difference between life and death for American citizens.

But one of those programs is going to sunset at the end of the year. I'm talking about section 702 of the Foreign Intelligence Surveillance Act. This is a program that collects information about foreign persons on foreign soil-and as a result saves American lives. Unfortunately, this and other programs were distorted in the public debate by a traitor, disgruntled ex-NSA contractor Edward Snowden, who now sits in the warm embrace of Russian intelligence services. And ever since his very damaging leak of classified material a few years back, many Americans have grown doubtful of these programs-and section 702 in particular.

Which is why it bears repeating just what section 702 does. It allows our national-security agencies to collect Internet or phone communications from a source within the United States-like an Internet-service provider-but only under a very specific set of conditions. It cannot target American citizens-not even lawful permanent residents. It can't even target foreigners communicating on U.S. soil. And it can only target people discussing a specific list of topics pre-approved by the FISA Court, which is made up of federal judges with life tenure.

And we're not talking about what they're picking up at the grocery store or checking in on the kids. We're talking about things like weapons of mass destruction.

It's true that this program occasionally does collect information about American citizens-and that will be true of any attempt to stop any kind of homegrown terrorism. But if you're concerned about protecting Americans' privacy rights, then you should support extending this program. It puts in place a host of privacy protections to scrub raw intelligence of any unnecessary identifying information. To allow this program to expire on December 31 would hurt both our national security and our privacy rights.

That's why today I'm introducing a bill that would reauthorize section 702 permanently, as is, with no changes. We can't tie the hands of our national-security officials at the precise moment that our enemies are taking the gloves off around the world. Terrorists don't plan to sunset their threats to our way of life, so why should important counterterrorism tools sunset?

I'm glad to say my legislation has the support of every Republican senator on the Intelligence Committee. And I look forward to earning the support of my colleagues in the weeks ahead-because we can't afford to let this program expire. It is not too much and it is not an exaggeration to say that American lives depend on section 702.