Trump has not built single mile of new border wall since taking office http://www.independent.co.uk/news/world/americas/us-politics/donald-trump-border-wall-not-built-2020-campaign-a9015181.html
But it doesn't matter. Trump talks about it ad nauseum, and his adoring loyalists believe that large sections are being built even as we speak. Facts no longer matter because his supporters do not believe objective fact.