A fall guy or a patsy! The real saboteur who was engaged in bringing Japan to war was his predecessor, Kimimaro Konoe (and his entourage).
You can tell this by looking at what happened at the Tokyo Trials. Navy officials had enough time to burn the documents and shut the mouths among them so that nobody provided enough evidence to prosecute almost any of them. And Konoe was relaxed as he had accumulated enough circumstantial evidence to convince that he had tried to avoid the war (although probably assassinated by those who had conflicting interests). And the dumb naïve Army officials did not conspire to kill the evidence.
What had Tojo done during the long period of the negotiations that Konoe pretended to have before leading to the war?