In his statement describing the Paris attacks as an "act of war" against France, President François Hollande said the war "was waged by a terrorist army, a jihadist army, by Daesh, against France."

Secretary of State John Kerry also referred to Daesh in Vienna at an international conference on Syria. This is not a term most Americans are familiar with, but it's part of a larger dispute — largely between Western governments and Western media outlets — over how to refer to the group we call ISIS, one that pits the strategic agenda of governments against the goals of clear communication.

A short guide to ISIS's many names

There are, broadly speaking, four things that people call the group: ISIS, ISIL, the Islamic State, and Daesh. This is largely ISIS's fault; a big reason the group has so many names is that it keeps changing it.

When the group's predecessor organization was created in 1999, it was called Jamaat al-Tawhid wal-Jihad, which means Unity and Jihad. In 2004, the group's founder, Abu Musab al-Zarqawi, pledged an oath to al-Qaeda, changing his group's name to Tanzim Qaidat al-Jihad fi Bilad al-Rafidayn — or, as it was called in English, al-Qaeda in Iraq.

After AQI took over huge swaths of Iraq in 2006, the organization declared itself to be a state in northern Iraq and started calling itself the Islamic State in Iraq. When it took a bunch of territory in Syria in 2013, it began calling itself the Islamic State in Iraq and al-Sham — ISIS.

Al-Sham is a difficult-to-translate Arabic term referring to a specific geographic area along the eastern Mediterranean that includes Syria. Some English speakers translate al-Sham as "the Levant," which refers to a broader region in the Middle East that generally overlaps with al-Sham. This is how you get ISIL (Islamic State in Iraq and the Levant), as the White House and others call it. Others still approximate al-Sham to Syria, which yields the same ISIS acronym.

The full name in Arabic is transliterated like this: al-Dawla al-Islamiya fi Iraq wa al-Sham — which produces the acronym DAIISH (usually spelled Daesh in English). That sounds an awful lot like the Arabic word "dahes," which the Guardian translates as "one who sows discord." ISIS kind of hates this insulting connotation, and so banned the name "Daesh" in its territory.

But it doesn't use ISIS either. Crucially, the group now claims to be a caliphate — that is, the successor of the original seventh-century founding Islamic nation. As such, it dropped the geographic identifiers from its name, and simply calls itself "the Islamic State."

The case for calling it "Daesh"

A lot of news organizations use "Islamic State" or "the Islamic State" for a simple reason: It's what the group calls itself, and accuracy is important. But politicians and governments generally don't. They've got some pretty good reasons: Calling it the Islamic State helps ISIS sell its message, and helps insult Muslims to boot.

The name "Islamic State," as opposed to ISIS or Daesh, is at its heart a propaganda tool. By claiming to be the caliphate, ISIS is implying that it's the only state true Muslims should obey: Around the world, they should pledge loyalty to the one and only Islamic State. This message is part of how ISIS recruits and thus keeps fighting.

Hence why British and French authorities are moving to the more derogatory Daesh, which doesn't imply that the group is either a real government or an authentic representation of Islamic thought.

"Islamic State, ISIL, and ISIS [give] legitimacy to a terrorist organization that is not Islamic nor has it been recognised as a state," 120 British MPs wrote in a letter to Lord Tony Hall, the director general of the BBC.

It seems unlikely that anyone joins ISIS because of the words David Cameron or Barack Obama, let alone a TV news anchor, uses to describe the group.

But there's also an issue of insulting and stigmatizing Muslims. Using the name Daesh sends the message to French and British audiences that they should not equate ISIS with Islam. Given the large Muslim minorities in both countries, and their struggles with assimilation and intolerance, this is an important message. A group of British imams wrote a letter to Cameron last year asking him to call it the "un-Islamic state."

Cameron, during a BBC interview, called the name Islamic State "a perversion of the religion of Islam, and many Muslims listening to this programme will recoil every time they hear the words Islamic State."

The case for calling the group ISIS

While it's Cameron's job to combat ISIS propaganda in the UK, it's the BBC's job to accurately inform its audience about ISIS as an organization: what it believes, how strong it is, what it wants, and, yes, what it calls itself.

For non-Arabic-speaking audiences, Daesh is merely another unfamiliar foreign word. But "the Islamic State" helps convey the group's core ideology: It sees itself as an Islamic government, not merely another terrorist organization.

Understanding this is critically important to understanding how the group works. It's also important for understanding how it's being fought. Because ISIS is ideologically committed to governing and defending its territory, it needs to fight a conventional war rather than an insurgency. This point is not well understood; most people think of ISIS as something like the Viet Cong or the Iraqi insurgents of the mid-2000s.

At the same time, "ISIS" is perhaps more accurate than "Islamic State" because, despite the group's efforts to sow violence in other countries such as Yemen and Libya, its claim to statehood only really stands in Syria and Iraq.

As for the issue of whether the last word in ISIS's name should be translated as "al-Sham" or "the Levant" or "Syria," there's not really a single answer. But one reason many organizations have stuck with ISIS over ISIL is that the former is by far the term readers are most familiar with, as this Google trends search emphasizes (ISIS is the one in blue):

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