We never get to the point to which the Saudi alliance is questioned at a fundamental level. The motte and bailey style 'debate' stays in the realm of whether or not the Khashoggi murder was bad, or on some other irrelevant side issue of the Saudi government's conduct. The problem, essentially, is our military alliance with Saudi Arabia. This is almost never debated. Only side issues such as Saudi women not being allowed to drive or Saudi use of the death penalty are ever allowed to be raised. It's considered 'unserious' to question the iron security guarantee that our republic provides to this royal family.
Saudi Arabia could turn 1 million Kahsoggis into meatballs and the American Op-Ed-Oligarchy would be unwilling to question the fundamental diplomatic issue of America's alliance with Saudi Arabia. We have already tested this commitment when a couple dozen Saudi nationals blew up the World Trade Center twice and the alliance with Saudi Arabia only strengthened as a response.
This would be like Gavrilo Princip killing Franz Ferdinand and the Habsburgs responding by increasing foreign and military aid to Serbia, encouraging Serbia to blow up more of its neighbors, then going to war on behalf of Serbia multiple times to increase its power and influence. 27D chess or corrupt-stupid-evil; you decide.