struck isis targets. >> russia has chosen to double down on their long-standing relationship with assad committing additional military hardware, capabilities and personnel. we have not for our part and will not agree to cooperate with russia as long as they continue to pursue a misguided strategy. >> reporter: relations with moscow made more tense with a dutch investigation concluding it was a russian-made and supplied missile system that shut down the malaysia passenger jet mh-17 over ukraine last july. donald trump waited into the mh-17 story appeared to express doubts about the certainty of you shall russian involvement and said you'll probably never know for sure and said the culprit was probably pro-russian fighters this differing not only with touch investigators that concluded it was a russian supplied missile but u.s. intelligence that determined very quickly after the crash