The author's point that the current power structures which exist in our world use the method of pitting different groups against each other is the specific takeaway that I wanted to spotlight. This is because it applies to virtually every challenge that liberal-minded people are trying to meet.
Now, I am no conspiracy theorist. I don't believe that X number of people meeting in some well-appointed boardroom are actually running the world. I absolutely and adamantly do NOT believe that "The Jews" are in control of the world. The various legal and financial systems that keep human society running along are impacted by 8 billion complicated souls and a physical universe that is beyond human control. Nobody is really "in charge".
That being said, there are various individuals and socially-constructed entities who have outsized power to affect the various human-crafted systems that maintain what amounts to the status quo here on Earth. Those people are motivated by profit and a sub-set motivation is the desire for control.
One way to maintain that control and keep raking in the profits is to hold the line against the social changes that seek to re-distribute those profits and allow people more control over their lives. Those powers-that-be limit our effectiveness in creating change by presenting false either/or narratives.
Take the lead up to the Civil War in America. Many of the abolitionists were also suffragettes. (And some of those women were racists, I will not deny that.) At that time in American history there was an unspoken choice to be made between ending slavery or securing voting rights for women. It's not as though some people didn't want to see both happen, but it's almost as though some limit of the human imagination could not accept both changes simultaneously within the shared zeitgeist.
Ending slavery became the prevailing cause and it was the correct choice. However, there is no legitmate reason why the people supporting both causes could not achieve those ends at the same time.
The people holding power will cede as little power as possible to the people fighting for it. Fallible humans that we are, most of us only have the energy to focus on one front at a time. Thus, the power-brokers play us off against each other.
It is possible to want the people in Israel to be safe and the people in Palestine to be safe as well. It is possible to against Antisemitism and Islamophobia at the same time. It is possible to support women's causes and also support men in their quest for mental health in opposition to a patriarchal system that treats women as sub-human and expects men to be superhuman in the face of normal feelings as they struggle with a complex world that makes it hard to just be a person. It is possible to see Black people's lives uplifted with access to all sorts of resources without taking away those resources from poor White people are any other group.
It is only the people who are hoarding the money while trying to control our lives to keep us poor and frightened and overwhelmed who are telling us that there isn't enough money or freedom or dignity to go around. We have to stop "othering" each other. Chances are that anyone reading this wants a few basic things for themselves and the people whom they consider their "in-group". Well, I want those same things for myself and the people whom I love. I don't begrudge anyone the right to be safe. I do begrudge those who are protecting the safety of their extra billions of dollars at the cost of a world on fire.