Is that something we know? I'm trying to check that out. I see this from September 8th at the Washington Examiner:
Hillary Clinton said Thursday that the Islamic State wants Donald Trump to win the presidency because he would be a weaker leader, and she also reiterated her pledge to keep ground troops out of the Middle East during her first press conference in 2016.Would ISIS want a ground war? In any case, Trump hasn't promised a ground war. He's only said it's foolish to take anything off the table. What is the authority for Clinton's statement except Clinton herself? Who is this "national security expert" and did he somehow know what ISIS leaders want?
Clinton cited an article by a national security expert that argued the Islamic State "supports Donald Trump".... "I think putting a big contingent of American ground troops on the ground in Iraq and Syria would not be in the best interest of the fight against ISIS," Clinton said after reporters suggested her unequivocal pledge to keep troops out of the region could box in her strategy. "I think it would fulfill one of their dearest wishes, which is to drag the United States back into a ground war in that region," she added.
I found "Why ISIS Is Rooting for Trump," by Mara Revkin and Ahmad Mhidi in Foreign Affairs:
[I]nterviews with ISIS supporters and recent defectors suggest [that] jihadists are rooting for a Trump presidency because they believe that he will lead the United States on a path to self-destruction. Last week, an ISIS spokesman wrote on the ISIS-affiliated Telegram channel, Nashir, “I ask Allah to deliver America to Trump.” Meanwhile, an ISIS supporter posted on one of the numerous jihadist “channels” hosted by the Telegram messaging application, “The ‘facilitation’ of Trump’s arrival in the White House must be a priority for jihadists at any cost!!!”Okay, so a "spokesman" and a "supporter" supposedly said something. Should we trust them to tell the truth? Why would they give a useful argument to a candidate it didn't want to win? It would make more sense to interpret the evidence as a preference for Hillary.