NBC News Signal - November 29th, 2018

As world leaders assemble in Buenos Aires for the G-20 Summit, a simmering trade war – not to mention the price of the iPhone, steel, and many crops – are on the line. The scientist behind the climate assessment that Trump questioned sets the record straight. Six thousand migrants are still in a stadium in Tijuana; we’re live from the San Ysidro port of entry. And, how a small shift in policy at the Department of Agriculture could lead to a dark fate for 4,000 wild horses.