Moving outside the issue of whether all Trump supporters are afflicted with both Dunning-Kruger Syndrome AND motivated reasoning disorder, which we should not debate here…
There is strong evidence that most cetaceans are intelligent at a very high level…across many of the touch points that we consider key for being sentient including pain. I’ve seen some studies that indicate the cetans might will be able to plan ahead based on probability and learned experience.
Also have seen some articles regarding the highly developed social structures of elephants, specifically the African plains elephants. Evidence of historical thinking, caring for sick and elderly and some sense of grieving is indicated. Also, teaching behaviors beyond just predation is nearly at intuitional levels.
As has been pointed out, below the Chordata level, there is pain sensing and pain avoidance…so I am not so sure that is evocative of sentiency or a primitive fight/flight reaction.
One final thought…who should define sentiency…humans or the beings we believe to be sentient? Speculating for a moment—Cetans are most certainly operating at a much higher level than most other species. Given that homo sapiens sapiens has basically brought a number cetan species to the verge of extinction, wonder if they would rank US much above primitive tool users incapable of peaceful co-existence with other intelligent beings.