evidence: North Toward the Yalu River [...] MacArthur swiftly ordered his troops to advance across the 38th parallel toward the North Korean capital of Pynongyang, where the 1st Cavalry Division arrived on October 19. Meanwhile, South Korean forces, on the general’s orders, streamed toward the city of Unsan on the way to the Yalu River, which separated China from North Korea. [...] On November 24, MacArthur launched a massive offensive toward the Chinese border. Almost on cue, hundreds of thousands of Chinese troops stormed across the Yalu River from the north, sending US and UN troops into frantic retreat. The scope of the invasion was breathtaking. Julius Becton Jr. recalled: