His first instincts are again correct
Trump's Ambassador to the UN, NATO and Germany have singled out Russia as to blame for the naval clash with Ukraine Sunday:
At a UN meeting, Ambassador Nikki Haley condemned Russia’s actions as “outrageous,” and said they amounted to a “violation of sovereign Ukrainian territory.” That does not appear to be the case, even in the Ukrainian government’s version of events.
NATO officials also expressed “full support” for Ukraine, and reiterated complaints about the 2014 Crimean secession from Ukraine, and subsequent accession into the Russian Federation.
German officials also issued a statement, saying it was “unacceptable” for Russia to block off its own part of the Sea of Azov, and that they consider the matter worrying.
The President of the US has so far declined to do the same:
President Donald Trump says the U.S. doesn't approve of escalating violence "either way" between Russia and Ukraine.
Speaking publicly for the first time after a weekend naval confrontation off the disputed Crimean Peninsula raised tensions anew in the volatile region, Trump is not specifically calling out Russia's behavior.
Says Trump, "We do not like what's happening, either way, we don't like what's happening and hopefully it will get straightened out."
Seeing how this summer Ukraine was able to sail its warships through the Russian-controlled Kerch Strait after asking permission from the Russian side, it seems obvious the shooting incident could have easily been avoided had Kiev been willing to do so again -- instead the Ukrainian side embarked on a mission to force entry without permission which they knew would be unacceptable to the Russian side.