US Defense Secretary Jim Mattis will deliver an address at an international security conference today. Attention is focused on the Trump administration's stances on North Korea's nuclear and missile programs as well as China's increased assertiveness in the South China Sea. The Asia Security Summit, also known as the Shangri-La Dialogue, opened yesterday in Singapore.<br/><br/>Defense ministers and other officials from the Asia-Pacific region are attending the 3-day conference. Australian Prime Minister Malcolm Turnbull gave a keynote address yesterday. He mentioned the US pullout from the Trans-Pacific Partnership free trade pact and expressed his concern that the United States may reduce its engagement in Asia.