Edward Snowden (Barton Gellman for The Washington Post)

We're now just 15 months removed from Edward Snowden's first bombshell revelation about the United States' massive surveillance apparatus. But with Islamic extremists putting down roots in Syria and Iraq, Americans are very much reverting to a pre-Snowden attitude toward civil liberties.

Or perhaps we should call it "post-Snowden."

While the Snowden revelations led to a lot of American soul-searching when it came to just how much of our civil liberties we want to yield in the name of protecting ourselves from terrorism, the soul-searching has largely come to an end, according to a new poll.

The Pew Research Center poll shows 50 percent of Americans say the government has not gone far enough to protect the country, while 35 percent are more concerned about the government going too far to restrict civil liberties. That's the most pro-security posture Americans have had on this question since 2009 and one of the highest on record since Sept. 11, 2001.

In contrast, 10 months ago, in the midst of several big Snowden leaks, significantly more Americans favored the civil liberties emphasis (47 percent) over taking additional steps to secure the homeland (35 percent).

The reason for the shift? People are scared.

An NBC News/Wall Street Journal poll this week showed fears of American vulnerability to an attack is at its highest level since 9/11. Fully 47 percent of Americans think we're less safe than we were before 9/11 -- a scary thought if there ever was one. Only 26 percent say we're more safe.

A Washington Post-ABC News poll, meanwhile, showed 91 percent of people view the Islamic State as a serious threat to the United States' vital interests (not the same as a direct threat, I would note). About six in 10 (59 percent) say the extremist group is a "very serious" threat.

Given that very real fear, it's perhaps not surprising to see people willing to cash in some of their civil liberties in exchange for peace of mind when it comes to their safety.

But it also suggests the shift toward civil libertarianism and the criticism of the National Security Agency in the aftermath of all the Snowden revelations -- of which more could certainly come and change things again -- were very temporary. Kind of like the GOP's brief flirtation with non-interventionism.