Charlie Winter is senior Research Fellow at the International Centre for the Study of Radicalisation. The opinions in this article are those of the author.

(CNN) One week into the US-backed offensive to retake Mosul , Republican presidential candidate Donald Trump claimed that it was "turning out to be a total disaster." There is a lot wrong with this statement -- first and foremost, the fact that it was simply not true. In reality, after just seven days of fighting, ISIS had lost hundreds of square kilometers and coalition allies were within five miles of Mosul's city limits.

Contrary to the Trump take on things, the operation had gotten off to a good start and, about this, there was almost universal consensus. Even the Russians expressed their cautious optimism.

The attack on Mosul is turning out to be a total disaster. We gave them months of notice. U.S. is looking so dumb. VOTE TRUMP and WIN AGAIN!

When it comes to Mosul, Trump seemed to be on his own. And he would have been, were it not for ISIS, the position of which he had unwittingly reiterated almost word for word. Indeed, four days before the tweet in question, the ISIS propagandists published their weekly newspaper leading with the headline , "An Unsuccessful Start to the Crusader Campaign against Nineveh," and claiming that the operation was doomed to failure from the outset because it was driven by "the necessities of the presidential election campaign in America," rather than a real will and tactical capability to liberate Mosul.

That Trump was on the same page as ISIS may seem strange, but it is not surprising. After all, a large amount of Trump's appeal relies on the pretense that everything is going wrong and that only he can save things. Hence, if he were optimistic about Mosul, he would have risked undermining one of the core pillars of his entire campaign.

Notably, though, this is not the first time that Trump and ISIS have seen eye to eye. Indeed, over the last year in particular, his rhetoric has persistently reflected that of the ISIS propagandists , especially when it came to issues pertaining to Islam and the West. It's in this context that the similarities are most striking: when Trump says "I think Islam hates us," ISIS is there to back him up as evidence, declaring that "we [and the religion of Islam that ISIS falsely claims to represent] hate you."

At times, it is almost uncanny how closely each affirms the other's worldview. However, this is not because their ideological positions actually resemble each other, and it is certainly not because an active relationship exists between the two. Not by any stretch of the imagination could that be the case.

Rather, this strange symbiosis is just indicative of the fact that opposing extremisms sometimes work in each other's favor: the fear that drives Trump's anti-Muslim populism , in a not-so-roundabout way, fuels the fires of ISIS' global jihadist project. While their goals are poles apart, each appeals to their supporters by stoking fears of the "other." So, when ISIS says the West hates Muslims and Trump says Muslims hate the West, they end up reinforcing and reaffirming the other's system of beliefs.

In both instances, the ideological adversary and the fear it inspires end up serving as a resource to be tapped in order to back up bombastic claims and rally supporters around the anti-"other" cause.

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While it's most certainly unwitting on Trump's part, the same cannot be said of ISIS. After all, despite some reports, it has not once mentioned Trump in its official propaganda, at least that which it circulates on the Internet. Perhaps, then, this is because its propagandists are begrudgingly aware of his potential as an evidence base for their assertions and, for that reason, do not want to get in his way.

After all, a Trump White House would be a real coup for ISIS. To have someone as polarizing as him at the reins of power would, for ISIS supporters, be confirmation of the fact that there is an inevitable war against Islam , an unavoidable clash of civilizations

In any case, even if he loses the election, the unsuspecting Trump has already played into their hands. The damage his campaign has done with its rampant normalization of anti-Muslim hate will be with us for a long time.

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Whatever happens on Tuesday, it is crucial we recognize that ISIS and its ideological associates have been working toward this for years now. Indeed, a desire to polarize is a fundamental part of their terrorist strategy . Intra-communal hate is a way to reify the jihadist worldview, a tool to eliminate the gray zone within which Muslims and non-Muslims cohabit and, ultimately, something that can fertilize the pools within which extremists seek to recruit.

In this sense, ISIS and groups like it have few more effective allies than the unwitting Trump and his loyal retinue of anti-Muslim rhetoricians.