Yes the US did start it and if a US boat did get blown up, I guess Trump will call that an act of War...... Then would it actually be a war, Cuba has no power unless of course China and Russia comes to it's aide, and I doubt it.

oh but wait they were US Cuban residents, to Trump nothing lost.

10 Cuban nationals on U.S. speedboat intended to carry out an 'armed infiltration,' Havana says https://www.nbcnews.com/world/latin-america/cuba-four-killed-us-boat-violates-territorial-waters-rcna260704