TOKYO, August 31 (Reuters) - Six months after Japan's premier bonded with Donald Trump on a golf course amid hopes he'd be a pragmatic partner, a consensus is emerging that Tokyo must reduce risks from the unpredictable president by forging ties with his more mainstream advisers. The increasing controversies surrounding Trump coincide with rising tension over North Korea's rapidly developing missile and nuclear programmes. It raised the tension again on Tuesday by firing a ballistic missile over northern Japan. Whether by design or default, Trump and his aides have sent mixed messages on North Korea, with Defense Secretary Jim Mattis saying on Wednesday Washington still had diplomatic options shortly after Trump tweeted that "talking was not the answer". Mattis is high on the list of people in whom Japan puts its faith, along with national security adviser H.R. McMaster, Vice President Mike Pence and "globalists" such as top economic adviser Gary Cohn, Japanese political officials say. "Of course, we are aware the Trump administration faces internal confusion domestically but we cannot let this shake the alliance in the current situation of tension," a senior official of the ruling Liberal Democratic Party told Reuters. "It is necessary to minimise the impact and to do that, we need close ties at every level ... By promoting multi-layered ties, we can minimise the destabilising factors." In the latest such effort, Deputy Prime Minister Taro Aso heads to Washington on Monday for economic talks with Pence. [nL4N1LF1MB] The hope is that by staying engaged on the economic front, Japan can prevent trade friction from Trump's "America First" policies from eroding a vital security alliance. "The risk with Trump is that he will link economic issues with security," said another Japanese source. "The victim at the moment is China, but there is no guarantee that Japan will not be among the victims." To be sure, Abe has kept close contact with Trump since his surprise November election, meeting the president four times and speaking to him 11 times by telephone, including twice since Tuesday's missile launch. The well-publicised calls are an important way to send a message to North Korea that the U.S.-Japan alliance is tight, two former diplomats said. 'STRANGE ... UNSTABLE' But while Abe has not been at odds with Trump publicly, early hopes that the billionaire developer's campaign rhetoric on trade and defence was mostly for show have faded. "At first I thought 'He's a businessman and he knows what he's doing'... But he's changed over the past half year. He seems to have become confident in a strange way," said another senior LDP official. "The Trump administration is very unstable and we're quite concerned." Trump's remarks blaming "both sides" for violence between counter-protesters and white supremacists at an August rally in Charlottesville, Virginia, have also raised some concerns. "To say discriminatory things that divide the American public touches on the core of the American people," the second LDP official said. "To split the American public is not a wise strategy ... It is very serious and it is a worry." With Japan ultimately reliant on the U.S. nuclear umbrella for its defence, the growing reach of North Korea's missiles has prompted concern about "decoupling" - the fear that Washington will be unable or unwilling to defend Japan if its mainland comes under attack from North Korean nuclear-tipped missiles. To assuage such worries, a joint statement issued after an Aug. 17 meeting of the allies' foreign and defence ministers reconfirmed U.S. commitment to protect Japan "through the full range of capabilities, including U.S nuclear forces". Japan has also sought assurances that Trump will not launch a strike against North Korea without consulting Tokyo. "I think if the U.S. were to take action, it would consult Japan beforehand," the second LDP official said. "But I don't know."