The term "dispossessed" has interesting meaning here. 

Most would automatically think of material dispossession - i.e., home, job, finances, etc. Now we know that some of the Trump supporters are low income or disenfranchised people, but we also know that his supporters average an annual income of 72k per year, USD. That's not chump change. 

So perhaps it is dispossession of another sort that bothers them. Like not being stationed at the top of the social hierarchy anymore, simply by virtue of being white "Christian" Republicans. The world order now visiting their neighbourhoods has changed the face of their country forever and they are struggling to keep up. Watching the behaviour of some of them at Trump rallies, they struggle to stand upright.
Wonder how this dangerous dynamic would change if they chose instead to not see themselves as victims and reject Trump's selfish manipulation of them. Sad!