Fortinbras seems like kind of dick.
He swoops in to attack Denmark over an old argument at the first sign of political shift and tries to do it without his uncle knowing. He makes an attempt to make one preparation for war look like another, so his sick uncle is fooled. It’s kind of treasonous when you get right down to it. But, of course, in a few lines, we’ll see that Fortinbras isn’t punished for this action – just rewarded for stopping it. Spoiled dickish Fortinbras.