The Russian government obviously poisoned Navalny. They’re barely trying to hide it. The continued use of the same obscure poison is a clear message to Putin’s opponents–we’re coming for you, and you can’t stop us.
Trump, as you would expect, has been silent on the issue. If he did actually respond, he would probably say that the 400 pound guy on his bed might be responsible, or that America poisons its enemies, too.
American exceptionalism, indeed.