The devastating terrorist attacks of Sept. 11, 2001, were such a monumental moment in recent U.S. history that it's tempting sometimes to divide American popular culture into "pre-9/11" and "post-9/11." Tempting, yes — but not so easily done. Looking back, it's surprising just how many TV shows that we tend to identify with the '90s actually aired a sizable chunk of their episodes after the World Trade Center towers fell. Friends, Frasier, ER, Law & Order, NYPD Blue … They all carried on the spirit of the decade in which they were born, in an era when the world behind the television screen suddenly felt very different.

That schism between the seemingly benign atmosphere of America in the '90s and the "we can die at any moment" anxiety of the '00s is the subject of The Looming Tower, Hulu's miniseries adaptation of Lawrence Wright's book about the U.S. intelligence-gathering errors — and the stealthy forces of international malevolence — that led to 9/11. The differences between the '90s and now also serve as subtext to both series so far of American Crime Story (both the multi-Emmy-winning hit The People v. O.J. Simpson, and the more under-the-radar The Assassination of Gianni Versace), as well as Law & Order True Crime: The Menendez Murders, Manhunt: Unabomber, Unsolved: The Murders of Tupac & the Notorious B.I.G., and Waco.

During the past few years, we've been living through a boom-time for true-crime stories, with the podcast Serial and the TV docu-series Making a Murderer and The Jinx fueling the phenomenon. And thanks to the huge success of The People v. O.J. Simpson (and the Oscar-winning documentary O.J.: Made in America, which aired in five parts on ESPN around the same time), trend-chasing TV producers have been on the lookout for more tales of murder and scandal, drawn from an era that its target audience might remember.

There's undeniably something cynically opportunistic about this sudden boom. It's not like Law & Order creator Dick Wolf backed an L&O-branded miniseries about Erik and Lyle Menendez because his writing team (led by René Balcer) had something profound to say about American life in the mid-'90s. The calculation for pretty much of all of these shows has likely been something like, "Boy, people really tuned in for those O.J. things ... how can we get in on that?"

But here's what's surprising: Pretty much all of these series have been good.

Law & Order True Crime is the weakest of the wave (so far, at least), and even it has a lot to recommend: in particular an A-list cast, including Edie Falco as the Menendezes' lawyer Leslie Abramson, and supporting roles filled out by the likes of Anthony Edwards, Julianne Nicholson, Josh Charles, and Heather Graham. At times these post-People v. O.J. shows have felt like they could've been made in the '90s. They're star-studded throwbacks to the days of expensive Emmy-bait TV movies and miniseries.

Otherwise though, The Menendez Murders lacks the ambition of its contemporaries. A lot of the critical buzz for The People v. O.J. Simpson had to do with the chances the creative team took — from casting celebrities who peaked in the '90s, to spending entire episodes focused narrowly on individual figures or incidents related to the Simpson case.

The Assassination of Gianni Versace has been even bolder. To tell the story of how serial killer Andrew Cunanan (played with impressive oiliness by Glee star Darren Criss) murdered five men in four months, the show begins with him shooting the famed fashion designer Versace (Édgar Ramirez), and then moves roughly backwards in time episode by episode, amplifying the tragedy by showing Cunanan getting less desperate and more hopeful. More to the point, The Assassination of Gianni Versace very purposefully portrays the more underground nature of gay culture in the '90s — when AIDS was more of a danger, "outing" could kill a career, and marriage was out of the question.

Unsolved: The Murders of Tupac and the Notorious B.I.G. isn't as controlled as either of the American Crime Story series, but it deserves more attention than it's gotten from critics and telephiles. The series — which airs its finale on Tuesday — bounces between three timelines, simultaneously telling the stories of the rappers' decaying friendship, and the way two separate investigations into their murders exposed some uncomfortable secrets about LAPD corruption and the ties between criminal gangs and the hip-hop industry. Once again, a stellar cast (including ace character actors Bokeem Woodbine, Wendell Pierce, Aisha Hinds, and Donald Faison) keeps a complicated production lively and watchable, as the writers strive to make a sensationalistic celebrity crime relevant to today, by showing how it relates to modern race relations and police overreach.

Perhaps the most pertinent of the recent batch of '90s true-crime series are the ones that deal directly with pre-9/11 terrorism on American soil. In Waco, Taylor Kitsch plays Christian cult leader David Koresh, and Michael Shannon plays an FBI crisis negotiator who tries to mitigate between two different kinds of clumsy, short-sighted authoritarians: his own impatient bosses and a charismatic evangelist. And in Manhunt: Unabomber, Paul Bettany plays the notorious anarchist gadgeteer Ted Kaczynski, who eludes capture for over a decade until the FBI (including a linguist/codebreaker played by Sam Worthington) figures out a way to track him though his own words.

Both of these shows take a refreshingly clear-eyed approach to their subjects. They neither justify nor excuse Kaczynski or Koresh's crimes. But they do try to explain them, and to draw lines between law enforcement's institutional failures and some preventable deaths. In that they have a lot in common with The Looming Tower, where Tahar Rahim plays a Lebanese-American FBI agent who helps his colleagues understand — too late — how poorly U.S. crime-fighting units have handled valuable intelligence about terrorist threats.

Our fascination with these prestige television projects is partly related to their gift of hindsight. For TV viewers in their 30s, 40s, and 50s, the likes of Waco, Manhunt: Unabomber, and The Looming Tower dredge back up half-remembered names and newspaper headlines, and fit them into a cultural context that we lacked the perspective to see at the time. How does the death of Koresh and his congregation relate to the siege at Ruby Ridge, or the Oklahoma City bombing? What does the attack on the USS Cole have to do with 9/11? These shows make the connections.

But there's also an element of uneasy nostalgia that makes so many of the series in this bunch work so well. Whether they're tying the ultimate outcome of these cases to police arrogance, bureaucratic in-fighting, deeply ingrained racism, celebrity worship, or the media's unwillingness to confront creeping extremism at home and abroad, what these shows are all saying is that the problems we're more conscious of now were all just as pervasive and pernicious in the '90s.

To some extent, these crime stories are exposing what we should've known back then. But they're also whisking us back to that more relaxed, carefree time, when we weren't constantly preoccupied with what was already poised to destroy us.