riyadh fail north korean missile test weekend attempt reclusive country provoke something u.s. defense secretary jim mattis say tuesday pledge unite state work china reduce tensions u.s. president donald trump take hard line north korean leader kim jong un rebuff admonitions china proceed nuclear missile program see washington others direct threat saturday north korea carry missile launch pentagon say fail blow almost immediately speak reporters way middle east mattis say recent test intercontinental ballistic missile still reckless move show work closely right chinese ... try get control aim denuclearized korean peninsula mattis say trump acknowledge sunday soft line take china management currency link help north korea unite state ally china work range responses north korea missile test u.s. officials say china speak north weapons test support u.n. sanction ban import north korean coal feb. 26 cut important export chinese media raise possibility restrict oil shipments north korea unleash provocations monday u.s. vice president mike pence put north korea notice warn recent u.s. strike syria afghanistan show trump administration resolve test trump administration focus strategy tough economic sanction possibly include oil embargo global ban airline intercept cargo ship punish chinese bank business pyongyang north warn nuclear strike unite state provoke say develop would launch missile strike mainland unite state officials experts believe time away master necessary technology include miniaturize nuclear warhead mattis say north korea missile test mean provoke