I'm always amused by how some intellectuals dehumanize the armed services, as if they were no more than mindless robots instead of humans with their own families and community ties.
This is an age-old problem with armies and has a similarly age-old solution: just send soldiers from one community to police other communities. For example, during the Tienanmen Square Massacre, some Beijing-based units refused to fire on protesters, so units from further away were called in instead.
That is not nearly so uncontested, not even in the US. Did you forget how all the tech bros went to Trump's inauguration, bowing their heads and kissing the ring? With Trump being very small fry on the scale of "capital-owning class" this means there are other factors at work than just wealth dominating politics.
Also, the situation gets much more unclear in other countries. Otherwise, why wouldn't the most capital-friendly party rule in each and every country?