Do you wonder about the media's claims that there is no reason for Trump to send troops to the border if the Caravan won't be here for a while?

For all the badgering that the media has done over why it must be politics that Trump has put the troops on the border before the Caravan actually arrived (see above video), the New York Post provides the obvious explanation:

As three separate migrant caravans slowly made their way north through Mexico on Saturday, newly arrived US troops worked to lay a barbed-wire fence along the Texas side of the Rio Grande. 

The soldiers worked with US Customs and Border Patrol officers to lay about 1,000 feet of fencing along the river, the Defense Department said. The makeshift barrier was installed underneath the McAllen-Hidalgo International Bridge, which crosses into Mexico. The overpass is in the small town of Hidalgo, about 250 miles south of San Antonio. . . .

They are setting up fencing at the border.