Though renowned mostly for his work as a cinematographer — he won Oscars for his work in “Who’s Afraid of Virginia Woolf?’’(1966) and “Bound for Glory’’ (1976) — Haskell Wexler, who died last Sunday at the age of 93, directed films as well.

They include the documentary “Underground’’ (1976) about members of the revolutionary group the Weathermen, then fugitives for justice. Always a politically activist liberal, Wexler found himself on the receiving end of federal subpoenas to turn over his footage. With the help of such Hollywood pals as Warren Beatty, Jack Nicholson, and Shirley MacLaine, Wexler managed to get the subpoenas repealed.

He also made the drama “Medium Cool’’ (1969), a movie that captured the mood and turmoil of the time — it was filmed in 1968 in Chicago during the violent demonstrations that erupted at the Democratic National Convention. That film has had a lasting influence on the documentary genre with its incorporation of actual event footage in a fictional story.

In the end, the film turns the camera on itself, literally and metaphorically, and on the ethics and power of the news medium. We could use a film like that to scrutinize the media of today.

“Medium Cool’’ is available from Criterion on Blu-ray ($31.94) and DVD ($23.96). For more information go to www.criterion.com/films/28426-medium-cool.

On musicians dying young

Why is 27 the expiration age for so many brilliant pop stars? Four who died at that age have been profiled in documentaries recently. The films include Brett Morgen’s “Cobain: Montage of Heck,’’ about Nirvana founder Kurt Cobain; Asif Kapadia’s “Amy,’’ about Amy Winehouse; John McDermott’s “Jimi Hendrix: Electric Church’’; and now “Janis: Little Girl Blue’’ by Amy Berg (Oscar nominee in 2006 for “Deliver Us From Evil’’), about Janis Joplin, who died in 1969 of a drug overdose.

Of this group, Joplin probably had the most in common with Winehouse. Both had perhaps the most powerful and supple voices of their generation. Both had a hard time handling the stress and temptations of early success, and both succumbed to substance abuse.

Perhaps the major difference is that Joplin seemed to enjoy herself in the process, as can be seen in her tortured and rapturous rendition of “Ball and Chain’’ at the Monterey Pop Festival in 1967. It’s included in Berg’s documentary. Looking on with awe at Joplin’s performance is Mama Cass Elliot of the Mamas & the Papas, no vocal slouch herself, who would also die tragically young — in 1974, at the age of 32.

The film screens for a week starting Friday at the Regent Theatre in Arlington. The opening night will also feature a live performance by Kate Russo, former member of Joplin’s best back-up band, Big Brother and the Holding Company. Showtime is 7:30 p.m.

For more information go to www .regenttheatre.com.

Chuck vs. Ceausescu

They may not be great works of cinema art, but the films of Chuck Norris and Sylvester Stallone contributed to the overthrow of a communist tyrant.

So contends Ilinca Calugareanu’s documentary “Chuck Norris vs. Communism.’’ In the 1980s, Romanian dictator Nicolae Ceausescu sealed off the country from all Western media, including movies. But stalwart black marketers smuggled in thousands of forbidden films, and gung ho action fare proved the most popular.

Was it the anti-communist zeal in Norris’s “Missing in Action’’ (1984) or Stallone’s “Rambo: First Blood Part 2’’ (1985) that inspired Romanians to overthrow Ceausescu in December 1989? Or was it the glimpse of the nice cars, bountiful grocery stores, and other benefits of the capitalist system that they were denied?

In either case, Sly and Chuck’s oeuvres probably did not inspire the grim and brilliant pictures made by New Wave Romanian directors such as Cristi Puiu or Cristian Mungiu.

“Chuck Norris vs. Communism’’ airs Monday at 10 p.m. as part of the PBS series “Independent Lens.’’ For more information go to www.pbs.org/independentlens.

Netanyahu vs. Obama

“Frontline’’ film “Netanyahu at War’’ by Michael Kirk seems like a sequel to the series “Obama at War’’ broadcast last year. This latest film leads one to believe that the two leaders’ biggest enemies might be themselves.

Kirk begins with one of many low points in their relationship — Benjamin Netanyahu’s appearance before the Republican-dominated Congress denouncing Barack Obama’s nuclear treaty with Iran. His speech got so many standing ovations the place looked like a Zumba class, but in the end the treaty was upheld, and Netanyahu’s relationship with Obama became even more dysfunctional.

How did it get to this point?

As the film points out with its smooth assemblage of archival film, TV news reports, and talking heads (a balanced assortment from both sides that seems to omit only Netanyahu and Obama themselves), it would seem from their origins that the two should have gotten along quite well. Netanyahu grew up in the US and fell in love with its people, culture, and system of government. Obama started out in Chicago politics, where his biggest supporters and closest allies were Jewish.

But Netanyahu’s father was an ultra-conservative historian whose pessimism and mistrust shaped his son’s politics and philosophy. And Obama, gifted at reconciling disputes and seeking compromise, was, at least according to Netanyahu and his followers, dangerously naive.

“Netanyahu at War’’ asks both sides to ponder their positions and try to find out how they reached such an impasse. But leaves some questions unanswered and unasked. For example, it passes over the eight years of the George Bush administration with scarcely any comment. There’s little mention of the wars in Iraq or Afghanistan. And what were the conditions of the treaty which Obama said was the only way of keeping the peace and Netanyahu denounced — in that notorious Congressional address — as “a bad deal?’’

These omissions notwithstanding, “Netanyahu at War’’ is essential viewing for anyone interested in avoiding Armageddon. It can be seen on PBS and online, Tuesday at 9 p.m.

For more information go to www.pbs.org/wgbh/frontline/film/ netanyahu-at-war.

Peter Keough can be reached at petervkeough@gmail.com.