The debate over whether it's a good idea to use phrases like "Islamic extremism" in fighting global terrorism took center stage last week as the White House hosted a summit to discuss what it generically calls "violent extremism."

In a speech last Thursday at the summit, President Obama explained his rationale for eschewing references to terrorist groups' Islamist ideology.

"Al Qaeda and ISIL and groups like it are desperate for legitimacy," he said. "They try to portray themselves as religious leaders -- holy warriors in defense of Islam. That's why ISIL presumes to declare itself the 'Islamic State.' And they propagate the notion that America -- and the West, generally -- is at war with Islam. That's how they recruit. That's how they try to radicalize young people. We must never accept the premise that they put forward, because it is a lie. Nor should we grant these terrorists the religious legitimacy that they seek. They are not religious leaders -- they're terrorists."

So accurately describing their ideology, or calling the terrorists "jihadists" grants them undo legitimacy as true representatives of the faith, the argument goes. The current policy aims to deny them that mantle.

That's a theory. But there's a key question no one seems to be asking: Does it work?

This is a continuation of a policy instituted during President George W. Bush's second term, meaning it has been in place for more than seven years. If it is indeed the right, best policy, advocates should be able to point to tangible evidence to show its value.

Arguably, the Islamist ideology has never been more popular, given the flood of foreign fighters making their way to Iraq and Syria to join the Islamic State, or Boko Haram's endless reign of terror in Nigeria. Hamas still enjoys strong support despite following policies which bring devastation to the people of Gaza.

And there is no mistaking the religious motivation driving these groups. Hamas is an acronym for the "Islamic Resistance Movement." Boko Haram translates roughly to "Western education is sinful." And the Islamic State has a whiff of religious affinity.

The Atlantic this month devoted 10,000 words to explaining the core Quranic ideology, with an emphasis on an apocalyptic prophecy, which drives the Islamic State's brutality. It "follows a distinctive variety of Islam whose beliefs about the path to the Day of Judgment matter to its strategy, and can help the West know its enemy and predict its behavior," Graeme Wood explains.

That's more challenging when that belief system is deliberately kept out of deliberations.

Jeffrey Bale, an associate professor who studies political and religious extremism at the Monterey Institute of International Studies' Nonproliferation and Terrorism Studies Program, called the continued emphasis on avoiding references to Islamic doctrine by Western leaders and pundits "absurd."

The policy has "not had any discernably positive impact on dealing with the threats that such groups pose," he said in an email to the Investigative Project on Terrorism. "On the contrary. The simple fact is that it is the Islamists, not Muslim moderates, who are winning the struggle for ideological hegemony throughout much of the Muslim world, and that Obama's efforts to positively 're-set' relations with the Islamic world have completely failed ... In short, there is no evidence that this constant pandering to Islamist activists, these embarrassing efforts to whitewash Islamic history and doctrines, and the foolish insistence that jihadist groups have 'nothing to do with Islam' have had any beneficial effects. They have mainly served to confuse Western citizens about the extent and nature of the Islamist threat."

Maajid Nawaz, a former radical who now tries to combat the narrative which fuels Islamist terrorism, argues the avoidance policy could be making things worse for everyone, including Muslims. In recent social media and television appearances, Nawaz, a co-founder of the London-based Quilliam Institute, calls it the "Voldemort Effect."

Islam is a religion, he writes. Islamism is the attempt to make the laws of the religion supreme over a society. That's the ideology that must be defeated, but that "cannot happen if you refuse to recognise it exists," he wrote in a social media post addressed to Obama that he signed "a constantly betrayed liberal Muslim."

If we dare not say its name, in other words, it can become more frightening to its foes and more alluring to prospective recruits.

In a recent appearance on Fox News, Nawaz expressed concern that this self-censorship actually makes life more difficult for the overwhelming majority of Muslims who reject terrorist brutality displayed by the Islamic State, Boko Haram, al-Qaida and others.

Non-Muslims in the West "they're just petrified," he said, "and that can lead to even more anti-Muslim hate crime. Because if they are unable to pinpoint specifically that we're dealing with the Islamist ideology, in their ignorance they blame all Muslims. And of course then all Muslims face a backlash. So I think it's better if we wish to protect mainstream Muslims from anti-Muslim hate crime to name the very specific ideology that we're talking about, which is Islamism, and distinguish that from Islam the faith.

Nawaz is offering a theory, just like the people who advocate the policy embraced by the Obama administration. There's a key distinction, however. As he describes in his autobiography, Nawaz helped recruit followers to Hizb ut-Tahrir, a group which dreams of a global caliphate and has been called a "conveyor belt" for jihadist terror. He knows which messages worked and which did not.

Some American Islamists showed last week that the Obama message is not working. They have criticized the White House summit as hostile toward Muslims despite the verbal contortions invoked to avoid that very reaction.

If we're going to focus on extremist violence, they argue, the bigger threat to America is from right-wing, anti-government movements. It turns out the Department of Homeland Security is concerned about violence from "sovereign citizen" movements who believe they are exempt from state and federal laws.

But it would be wrong to talk about that, Linda Sarsour and Deepa Iyak wrote Feb. 17 in The Guardian.

"One thing is clear: the federal government's one-note approach to countering violent extremism fosters distrust and hostility towards Muslim communities while disregarding threats to Americans' safety from racist hate groups in the country."

There is a key distinction, however. For the most part, sovereign citizen attacks are smaller scale, often erupting in what should be routine encounters with law enforcement officers. CNN cites a 2012 example involving a Louisiana traffic stop that led to a shootout between police and a father and his son.

What Islamist terrorists want, what they urge followers to carry out, are mass casualty attacks that can target specific groups deemed to have offended Islam or simply any place where many people gather.

The United States has rigidly followed a policy, going at times to uncomfortable lengths, to avoid putting a religious label on terrorism clearly driven by a rabid adherence to centuries-old Islamic theology. The uninterrupted flow of new recruits to the Islamic State indicates that the policy has not had the desired effect.

"American policymakers do not yet understand Islamism or what persuades young Muslims to join Jihad: sincere religious devotion based on the core texts of Islam, in particular early Islam's politicized and aggressive period in Medina (compared to Islam's spiritual and ascetic period in Mecca)," Ayaan Hirsi Ali, a former Muslim, writes in Time magazine.

"How does one tackle misguided religious devotion of young Muslims? The answer lies in reforming Islam profoundly—not radical Islam, but mainstream Islam; its willingness to merge Mosque and State, religion, and politics; and its insistence that its elaborate system of Shariah law supersedes civil laws created by human legislators."

For the West, the sanitized language and tap-dancing around the issue makes it impossible to fully understand the enemy's motivation, writes Robert R. Reilly, a senior fellow at the American Foreign Policy Council.

"You cannot go into a war of ideas without understanding the ideas you are at war with. Yet, throughout the two speeches, [Obama] never mentions the substance of the enemy's ideas once," Reilly writes. "...This is like saying, in World War II, that we were fighting the Nazi ideology, but never mentioning the thoughts of Friedrich Nietzsche, Alfred Rosenberg or Adolph Hitler. Or, during the Cold War, saying we are fighting the ideology of Communism, but never mentioning the ideas of Karl Marx, Lenin, or Stalin."

Rather than continuing to do the same thing and hope for a better outcome, perhaps it is time to listen to the Muslim reformers asking for a more honest, tough love approach. Terrorists are committing acts of barbarism daily in the name of Islam. That doesn't mean all, or even most, Muslim see the same commands in their faith.

It might delegitimize terrorists more to emphasize how most of their victims are fellow Muslims, and to clearly draw the lines between the terrorists and the hundreds of millions of Muslims who reject their savagery.

It's a theory, anyhow.