Can and should psychology be used in this way? Can we predict and control macro behaviour like voting intention using questionnaires?

For the 2016 US Presidential election, won by Republican Donald Trump, the company
Cambridge Analytica used data collected via the social networking site Facebook to establish which individuals in key states for the election were most likely to switch their votes to the Republicans. With this knowledge they were then able to target campaign marketing to those individuals in key areas and so have maximum effect on the outcome of the election.
The efforts were regarded as being a key factor in the Republican victory. There were many concerns around the ethics of using the data, but one the pieces of information used was personality data collected using measures of the Big Five personality inventory a staple and bedrock understanding of personality in psychology.
Cambridge Analytica were not the first to use psychology to predict the behaviour of people. Indeed, in the early 20th century IQ tests were used were to assign people to roles in the US army or determine entry to the country. Similarly, in the UK during the 70s and 80s  whether children were deemed suitable for a vocational career or academic career was measured at 11 years old using an IQ test, the 11+.
Jonathan Haidt’s (2013) moral foundations theory suggests that political differences can be explained by differences along six foundations. Similarly, nudge theory has been researched by governments to use to influence behaviour for some time .
Can and should psychology be used in this way? Can we predict and control macro behaviour like voting intention using questionnaires?

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