Left turn?, part 1

A few days ago, Andrew Gelman sent me a question from Elin Litman on a puzzling finding from the 2018 GSS.  He included my reaction in a post on his blog--this post is an elaboration of my remarks there.   The items which prompted the original question were about whether the nation was spending too much, too little, or about the right amount on "Improving the conditions of Blacks" and "assistance to blacks."  The means, with lower numbers corresponding to the "too little" end:

So opinions on both apparently made a big move in a "liberal" direction between 2014 and 2018.  The change from 2016 to 2018 might be partly the result of the change in administration:  responses to questions like this tend to move left with a Republican president and right with a Democrat.  But of course that doesn't explain the 2014-6 changes, which are very large.  Could it just be some kind of mistake?

I looked at the means for two other variables related to race:  "Some people think that (blacks/negroes/African-Americans) have been discriminated against for so long that the government has a special obligation to help improve their living standards; they are at point 1. Others believe that the government should not be giving special treatment to (blacks/negroes/African-Americans); they are at point 5. Where would you place yourself on this scale?" and "Some people say that because of past discrimination, blacks should be given preference in hiring and promotion. Others say that such preference in hiring and promotion of blacks is wrong because it discriminates against whites. What about your opinion - are you for or against preferential hiring and promotion of blacks?"  The means--again, low numbers mean more liberal views:

Again, there's a large move in a liberal direction on both opinions between 2014 and 2016, and a smaller move in a liberal direction between 2016 and 2018.  On all questions, opinions in 2018 are more liberal than in any previous year. 

Why would this have happened?  One possibility is that it had to do with Donald Trump--the interviews for the 2016 GSS started in April 2016, after it had become pretty clear that he would be the Republican nominee, and went on until November.  Maybe Democrats reacted against Trump by strongly affirming things that he seemed to threaten.  So I broke the means down by party identification.  In all cases, the changes were in the same direction among supporters of all parties, although larger among Democrats.  That is, Independents and Republicans also became more liberal on these issues between 2014 and 2018.  An example:

Until 2014, Democrats and Republicans had been moving in different directions, but between 2014 and 2018 they both moved towards the "special obligation" end.  That doesn't fit the idea that the change was a Democratic reaction against Trump. 

So what caused the change?  I'll address that in my next post.

  PS:  Steve Morgan made some similar points on Twitter.