Ubiquitous

So, casual Tolkien references continue to show up in what you might think unlikely places.
As, for instance, in the middle of a recent piece in The Guardian describing harassment tactics used online by anti-vaccine advocates against people who let it be known they support childhood vaccinations.  
Here's the quote, with the key phrase highlighted in bold:

“We are at the point where doctors are creating their own anti-vaxx social media attack response teams to help other doctors” . . .One such rapid response team is being organized by Dr Todd Wolynn and Chad Hermann, the CEO and communications director of Kids Plus Pediatrics (KPP) in Pittsburgh, Pennsylvania.“If you’re being attacked, we’ll light the signal fires of Gondor, and you’ll have pro-science, pro-vaccine cavalry come to your aid,” Hermann said of the nascent project, called  “Shots Heard Round the World”.And here's the link to the full article it came from:https://www.theguardian.com/technology/2019/feb/27/facebook-anti-vaxx-harassment-campaigns-doctors-fight-back
As with most other such references I've been coming across, this one is marked both by its appearance in a non-literary context and by the (no doubt correct) assumption that it needs no explanation, that the average reader will know what the author's talking about.*
--John R.--current reading: THE FALL OF GONDOLIN,   an old issue of LOCUS (Sept 2004)

*actually in this case that assumption applies twice, once when Wolynn & Hermann said the line and again when The Guardian quotes it.