BACK in 1976, all it took to bring the Korean Peninsula back to the brink of a war was a brawl over an attempt to trim a poplar tree. That escalated quickly into the death of two American GIs by ax-wielding North Korean soldiers. Three days later, with an aircraft carrier battle group and nuclear-capable B-52 bombers at the ready, the tree was chopped down. For sure, the Demilitarized Zone that divides the Koreas is one of most volatile strips of Cold War-style weirdness left on the planet. On Friday it was weirder than usual, with President Donald Trump's new top diplomat, Rex Tillerson, standing on one side of the North-South demarcation line with his coterie and North Korean soldiers standing at one point just a meter (a few feet) away. Tillerson's DMZ detour — which fittingly enough began at Camp Bonifas, an outpost named after one of the ax murder victims, Capt. Arthur Bonifas — came just a day after he called the past 20 years of US policy toward North Korea a failure and vowed a comprehensive policy review under Trump. In Seoul shortly afterward, the former oil executive declared previous President Barack Obama's North Korea strategy dead and told a news conference, "all of the options are on the table." In Tokyo the day before, he had said, "It is clear that a different approach is required." Trump, meanwhile, tweeted on Friday that "North Korea is behaving very badly. They have been ‘playing' the United States for years. China has done little to help!" So does Trump have some new formula for success? Tillerson's 20 years of failure assessment, while bleak enough, may actually be an understatement. Well before going nuclear, North Korea has dogged every US president since Harry Truman. The 1950-53 Korean War, fought under Truman, is technically still going, since it ended with a truce that has yet to be negotiated into an actual peace treaty. It was Gerald Ford who ordered "Operation Paul Bunyan," the massive show of force that followed the ax murder incident in 1976. Bill Clinton considered pre-emptive strikes in 1994, then tried increased engagement, which failed and was buried for good in 2002, when George Bush included North Korea in his "axis of evil" in a State of the Union speech. And despite Tillerson's tough talk — clearly aimed at reassuring Tokyo and Seoul — what path Trump will ultimately choose is a mystery. On the campaign trail, Trump said he was open to the idea of meeting directly with North Korean leader Kim Jong Un — flippantly adding that they might best talk over hamburgers. But he has also hinted at a hawkish approach or shifting the onus almost completely on to Beijing, which is North Korea's biggest trading partner and economic lifeline. In Tokyo and Seoul, Tillerson stressed that the policy review is underway and has suggested it will weigh the benefits and risks of the full gamut of foreign policy tools at Washington's disposal. That could range from pre-emptive attacks on its nuclear facilities and precision strikes aimed at killing its leaders to negotiation-based diplomatic engagement. For the moment, however, relations do appear to still be following the trajectory set by Obama, who focused on exerting pressure on the North through strengthening regional alliances, tougher economic sanctions in response to nuclear tests or missile launches and a flat refusal to talk without Pyongyang first taking concrete moves toward denuclearization. Even so, attention-demanding problems are increasing: The US and South Korea are currently holding their biggest-ever annual joint military exercises, which are seen by the North as a dress rehearsal for invasion. Washington and Seoul claim the maneuvers are purely defensive, but they bring a rise in tensions that increases the possibility of a clash, either intentional or in response to an accident or misjudgment in the field. North Korea just last week fired four ballistic missiles into the Sea of Japan, reportedly coming to within just 200 km of Japan's shoreline. The US and South Korea are planning to set up a state-of-the-art missile defense system known as THAAD, which along with the predictable opposition from Pyongyang has antagonized Beijing — Tillerson's next stop — because it can monitor activity in China as well. North Korea says it is in the final stages of developing an intercontinental ballistic missile that could reach the US mainland, and fit it with a nuclear warhead. More tests of both nuclear devices and long-range missiles are almost a certainly in the near future, though no one can predict when. For Tillerson and Trump — and for America's nervous Asian allies looking to them for leadership — acknowledging past failures will without doubt be a lot easier than formulating future successes with a country adept at playing the superpowers off each other and hell-bent on going its own way at almost any cost. — AP