The entirety of Lafayette Square was closed to the public as President Trump met with President Nazarbayev of Kazakhstan. Closures of this type, with their attendant increased show of police force, have become common under the new administration, particularly when the visitors have a reputation for authoritarianism. I suspect that, in addition to limiting opportunities for protests (which went a bit sideways when President Erdogan of Turkey visited), this demonstration of power over public space is a way the President can impress his more iron-fisted guests. The incident that happened with the reporters shortly after this photo was taken fits into that pattern as well.
