Before leaving the house, I find it helpful to imagine the median intelligence level in my geographic area (local, or country as a whole) and then recall that about half the population has a level below that point.
The issue isn't intelligence per se. It's ignorance (often willful ignorance), dogmatism, media illiteracy, political illiteracy, etc. There are many intelligent (but evil) people in the Trump administration and not every Trump voter is a dunce. Framing them all as stupid isn't useful, because it doesn't help us understand and counteract what's happening.