Previous posts in the Worldbuilding From Reality series are indexed here:
When you are worldbuilding, you are weaving the black velvet that will cradle and display your diamond. You are not creating the light that will make your diamond sparkle, or the diamond itself, but if you do a messy job of worldbuilding then no adjustments of light or cut of diamond will create the riveting effect you intend.
Worldbuilding is crucial, but should be as invisible as the black velvet of a jeweler's display case.
In this analogy, I'd guess the "light" is your theme, and the diamond is the Relationship you are depicting.
The Worldbuilding is an integral part of the light and the jewel it illuminates, and some genres, some authors, make the Worldbuilding into the whole plot. Done well, this is also riveting.
For example, the long running Destroyermen series by Taylor Anderson with the 2019 entry in the Series #14, Pass of Fire.
I can't sing the praises of Anderson's Destroyermen too loudly. The "world" is an alternate Earth (which a WWII Destroyer falls into from a storm in the South Pacific), and the building is how this tiny group of sailors orchestrates a reproduction of WWII, but with totally different factions, different species (some not human) and humans who fell into this world from different historic epics. We also have the indications some of the humans from different epics are actually from different parallel universes than our own.
So there is a cosmic-level worldbuilding theory behind the series, and the World where the conflict is in progress when our Destroyermen land there is the result of the asteroid that triggered the extinction of the dinosaurs landing in a slightly different spot, rearranging the geography of Central America.
There are a couple of species of feathered lizards that have achieved sentience -- and a civilization based on feeding the voracious populace both with humans and with their own species.
Our Destroyermen take the side of the people being attacked and eaten, or attacked and conquered by some stray WWII Japanese. Alliances form, war spreads, and the Destroyermen put the natives on the track of ever improved weaponry.
The 2029 entry in this Series is Pass of Fire (the fire being a series of volcanoes in Central America, the Pass being formed by the asteroid hit).
And from this base of intricate worldbuilding, the long-long sequences describing weapons improvements and what counter-improvements the enemies achieve (with the help of the Japanese), and what huge, world-wide, sprawling strategies and tactics can be launched, and which of the surviving Destroyermen are leading parts of the war, and which parts are led by those who learned from our Destroyermen, also describe the Relationships developing because of the battle-camaraderie.
The Characters gradually emerge as well rounded, understandable individuals with unique talents brought forth by vicissitudes. But even the marriages and births are incidental, except as one more motive to fight.
Survival is the biggest motive for this war.
Hollywood romanticized WWII by telling many deeply romantic stories about couples meeting during war, or separated because of it. War impacts real lives, reshapes life directions.
In an Action Genre, the war itself and how to conduct it, is the story and the plot.
In Science Fiction the science of war is shown as the key to winning.
In Romance, the impact of war on family relationships, and the highly intensified Romances sweeping people into Relationships they would never have chosen, is the Story while the war itself (strategy, tactics, weaponry advantage, resource allocation) is just background. The Romance-During-War Novel Plot is not the war, but the insane chances people take to get back together.
The Destroyermen series has no Romance in it, but it does have a few plausible Love Stories woven through it.
A Romance writer should read this series to study techniques for weaving flawless, featureless black velvet.
The last thing an artist wants is to distract the viewer's attention from the work of art being displayed.
In a Romance novel, the Jewel being displayed, the work of art, is the evolving Relationship. As the Relationship matures into Love through many classic stages (each experienced uniquely), the "action" unfolds on the field of Relationship. What the couple will do next is the suspense line. If they are soldiers in a war, which side wins the war is usually not the problem. If they are running the war, they win it together as a team.
In Romance, the war happens only to fertilize and inform the Relationship.
In the Action Science Fiction genre, which the Destroyermen Series precisely nails to perfection, the Relationships happen only to infuse the winning spirit into the combatants.
I have found not one single flaw in all of the novels in Taylor Anderson's Destroyermen Series.
I've discussed a few previous novels in this series:
And we discussed Pass of Fire in the Theme-Plot Integration series.
Clearly, I can't stop raving about Destroyermen. It's flawless, for what it is, but that just whets my appetite for a similar series, complete with intricately perfect worldbuilding, the science of weaponry, all used to create and showcase the developing of Relationships.
We are enjoined to love our fellows as ourselves, but we humans often fall short of that goal. The way Romance genre can illustrate the moves, strategy and tactics of warfare might teach us what there is to love in every human.
Romance writers need to study the Art of War as illustrated in the Destroyermen Series to see how the worldbuilding doesn't make the Story, but this kind of worldbuilding from the realities of WWII could make a whopping good Romance. Just keep asking yourself what's missing. What's there is perfect - but what's missing is even more important.