A big part of it is the two-party political system. Why bother voting when you don't like either party? The proportional democracies in Western Europe routinely have voter turnouts around 80%. There is always some party whose views roughly align with yours, and your vote never goes to waste.
And yeah, the deliberate voter suppression in the US isn't going to help either. A lot less people are going to stand in line for multiple hours, compared to the "five-minute stop on my drive to work" stuff Europe is used to - not to mention the whole hassle with voter registration and voter roll purging.
And yeah, the deliberate voter suppression in the US isn't going to help either. A lot less people are going to stand in line for multiple hours, compared to the "five-minute stop on my drive to work" stuff Europe is used to - not to mention the whole hassle with voter registration and voter roll purging.