As originally conceived in the 1960s series, The Prime Directive would appear to be an allegory about American interventionism during the Cold War; specifically, Vietnam. The Directive makes the series unique perhaps in the SF genre. For by and large, the vast majority of novels and films about star-faring cultures run counter to this notion. The whole point of being an interstellar culture is to dabble in the affairs of others, especially if they are less developed. This is borne out broadly by everything from Smith’s Lensman series to Clarke’s 2001 to Lessing’s Canopus in Argos series to, most recently, Scott’s Prometheus.
In 2001, as well as other novels by Clarke, notably Childhood’s End, consciousness is so rare on the galactic scale that, when found, it must be nourished, rather than allowed to suffer the hazards of chance. Lessing follows a similar line, portraying the benevolent Canopians as midwives to lesser, struggling species, setting out to bring them along and instill in them their own high moral values, but failing in that mission more often than not. The whole series is a critique of empire and its tragic colonial wages. A film like Prometheus gives us a darker, gnostic view of alien intervention, with the Engineers merely tinkering with lifeforms across the eons, in much the same way we might experiment with bacteria or mice. The point here is that the genre repeatedly generates drama and high moral stakes precisely from staging what happens when higher races engage openly in colonial or technological policies of intervention. (Iain Banks’ Culture novels consistently explore this theme in what I’ve called elsewhere the sub-genre of “science fiction after Auschwitz”).
The Prime Directive is noble in a touchy-feely New Left sort of way, but what it leaves out is central – how do starships get built? In other words, what’s notably absent in Star Trek is any mention of the enormous giga-tera-peta-economy required to sustain such a society. Is it a post-scarcity one? That hardly seems likely. "The Original Series," "The Next Generation" and "Deep Space Nine" all allude to interstellar trade, albeit vaguely, and in the case of the lattermost, through the anti-Semitic trope of the Ferengi. The building of starships and the maintenance of a vast interstellar trade organization still seems to operate under a capitalist paradigm of plenty and lack.
So then the Prime Directive becomes an empty category of liberal intervention by way of non-intervention that’s symptomatic of such Great Society projects like the Peace Corps, CARE, and UNESCO, to name a few. What’s key here is the idea of “value.” The Federation seldom reverts to vulgar gunboat diplomacy. Instead, it’s main tool of persuasion is to present itself as the exporter of an unquestioned free market individualism. And since no interstellar culture could continue to thrive without expanding its potential future trading partners or else exploiting them to acquire reservoirs of raw material to fuel their expansion, these values stand in for the logic of capital. (This is the driving concern of Alastair Reynold’s very good Revelation Space trilogy, in which the internecine Dawn War is waged between starfaring cultures for the all too scant mineral resources available to them).
Gene Roddenberry’s original vision for Star Trek was “Horatio Hornblower in outer space.” Thus the spectacle – straining credulity, yet visually and dramatically exciting – of starships firing broadsides at one another at close quarters under poky human command, instead of super-fast computer-controlled combat waged over far vaster distances and at far greater velocities. It's a romantic vision that keeps intact the dominant illusion of capital, which is this: that it's people, rather than systems, which design and regulate our welfare.
There’s a lot made in the latest installment, “Into Darkness,” of ST’s peaceful mission. But in fact it’s always been a military organization. The crew of The Enterprise may be Boy Scouts, but they are colonial Boy Scouts all the same. The utopian idealism of the Prime Directive is just a smoke screen concealing the ruhtless logic of the market, whose final goal is to colonize the entire galaxy under the flag of unfree enterprise