Again a weird comparison to the fascist, religiously driven suicide bombers of the Empire of Japan. How were they justified? They served a racially and religious driven cause through terror, rape and total war in the name of their religious leader/god emperor/aristocratic oligarchy. They had a lot in common with the terrorists we're fighting today, really. Japan were the bad guys in WWII. They invaded their neighbors, killed and raped their way across the Asian mainland for decades, joined up with the Nazis by choice, and drew the US into a war with an indiscriminate sneak attack on American soil which lead to the deaths of servicemen and civilians alike.
The pacifist, "nukes are bad" Japan you know from your Japanese Animes is a relatively recent occurrence brought about by direct American military intervention. Trying to draw parallels between the Empire of Japan and Islamic fundamentalists is always going to invite unintended comparisons and conclusions. Unless you think what needs to be done is for the West to wage total war on ISIS for a period of years culminating in a brutal curb-stomping to serve as a warning to anybody else looking in our direction followed by systematic overwriting of the native government and society with a version more benign, even beneficial, to us. Which is not, I assume, what you're trying to advocate.