The plot would be something like this sci-fi scenario: starting over 100 years ago, beings from another world, one that is maybe facing its natural end, infiltrate Earth.  They do it quietly, unobtrusively studying our various continents and cultures.  They are smart beings and have an agenda.  They begin inserting ideas here and there, playing a giant, manipulative game to achieve their end — the destruction of the societies that live on this planet, the better to resettle their own populace here.

These beings are masters of subtlety, at least for the first 80 or so years.  But then they up their game, because their planet is endangered and not going to last much longer.  They accelerate their manipulations, seeding the natural tendencies of Earth beings to enhance greed in certain chosen people, while others get paranoia and violence.  They can't affect every single being, but they're strategic, infiltrating governments, media, and institutions of higher learning so that, eventually, all of society is affected as the educated become teachers to the youths, the televisions blare the media message, and the government starts down the destructive path on which we now find ourselves.

Their plan works perfectly.  Society starts to crumble, just as the beings wanted.

The plot is complex — these beings are very smart, capable of multi-tasking, and quite motivated to be ruthless.  They take so many seemingly disparate actions, none of us earthlings can ever see the whole.  Some people are fed delusions of grandeur, while deliberately made stupid enough to create nothing but chaos, destruction, and failure.  Wrong thought becomes normal, and the compulsion to destroy is given power and glory under the guise of saving the Earth.

If we are made to think that we are destroying our planet, it acts as great cover — everyone is guilt-tripped, self-doubting, worried, and preoccupied.  All the better to destroy our defenses against the coming invasion.  We believe we are destroying the Earth by populating it — hence the rationale for easy abortion, our lower impetus to procreate, and the now swarming masses migrating from one country to another, sowing ill health, changing demographics, and stressing systems that have stood for centuries.

The aliens create a perfect storm by introducing a virus into the mix.  All the seeds they planted come to fruition while we exist in a societal void — with our entire social structure shut down during the handy COVID years.  During that time, bit by bit, concepts like "climate change" and "gender identity" and aberrant "trans" life are elevated in importance by an absurd but growing "green new deal" mentality.

Image: Space ship (edited) by upklyak.

We go from a normal, healthy society with some deviation from the norm thrown in for color to something far less stable, where we promote the bizarre, break family structure, and no longer trust in the good faith of our demonstrably unstable and arrogant government.  Kept isolated from one another, masked, made powerless, we get an increase in the powder-keg of violent tendencies in the populace, played out in the destruction of cities strategically scattered over our country.

These things manifest differently in other countries.  China locks its population in, as does Australia, but here, in the USA, that won't work.  Here, where they haven't quite managed to take our ability for self-defense away, they settle for further randomizing violence and disempowering local authorities.  We get profoundly dangerous neighborhoods in which people routinely attack one another; strife fomented among ethnic groups; and, concurrently with the vilification of the police, loss of the means for control.  Police are to be "fried like bacon."  Why should they defend us citizens if we are attacked?

We have growing desperation and poverty as people's savings are turned to dust by inflation and the middle class disappears as the chosen few are massively enriched.  We have a poison "vaccine" injected into a good portion of society that is guaranteed to cause a gradual (at first) acceleration in illness and death, decimating society.  It also perpetuates a permanent state of "pandemic," since it destroys the body's ability to develop immunity to the virus it is supposed to protect us from.  Even worse, the stuff interferes with fertility, and the birth rate plunges to zero.

The most sophisticated societies are the most affected.  The most successful and affluent members of the upper-middle class, who most wholeheartedly embraced the killer "vaccine," are the first to perish.  Athletes drop on the field of play, and children develop aberrant types of myocarditis and hepatitis and cancer.  We dissolve, as a society, over a matter of a few decades.  The perfect solution for our invaders.

Those spared are the most basic, primitive societies, which didn't "vaccinate" so have no pandemic.  They are also least able to defend themselves against becoming enslaved to the soon-to-arrive new masters, who intend to live a great life of leisure on our planet.

If I were a novelist, I might write that book.  Would it be fiction?