2 0 1 8THE YEAR AHEADFrom North Korea’s nuclear program to sectarian strife in the Middle East, global security worries promise to make headlines in 2018. In the U.S., the White House faces policy challenges and an ongoing probe, while investors confront near-record asset prices. Here are some events to watch.Published Dec. 31, 2017 at 7:00 a.m. ETU.S.PHOTO: ROBIN LOZNAK/ZUM..