PresidentDonald Trump and his top advisers have said in recent weeks that the Islamic State group in Iraq and Syria has been all but defeated, following through on a campaign promise that he would significantly escalate the U.S.-led war against the extremist group.

"Thanks to the leadership of this commander in chief and the courage of our armed forces, ISIS is on the run, their capital has fallen, and their so-called caliphate has crumbled across Syria and Iraq," Vice President Mike Pence said Dec. 20 during a ceremony marking the passage of a tax reform bill through Congress, using an alternative name for the extremist group.

The war against the terror network, however, is far from over, even in Iraq and Syria, where it first declared its so-called caliphate and from where its fighters and leaders are now spreading to other faraway regions of the globe, from Southeast Asia to Africa to not far from U.S. shores.

Brett McGurk, the special envoy to the coalition fighting the Islamic State group in Iraq and Syria, told reporters at the State Department just before Christmas that the U.S. had made significant progress against the extremist network in 2017, but there is still work to do.

"Nobody who works on these problems would tell you we're popping champagne corks or anything," said McGurk, who began his position during the Obama administration and has continued under Trump. "This is not over, there is a long way to go."

Defeating the Islamic State group in Syria will require months more of fighting, McGurk says.

As defense and intelligence officials continue to find and kill members of the extremist network and combat its success in remotely attracting followers worldwide, here are some numbers on where the Islamic State group still operates and maintains power.

Iraq and Syria

For the campaign to defeat the Islamic State group Trump inherited a U.S.-led coalition that had already begun clearing out Mosul in Iraq and was beginning to surround Raqqa in Syria – both key cities in the extremist group's messaging.

In January, about 35,000 Islamic State group fighters were in Iraq and Syria controlling more than 17,000 square miles – an area roughly the size of Pennsylvania. Now, between 1,000 and 3,000 extremists are occupying less than 2,000 square miles, according to officials at the U.S. military headquarters in Baghdad overseeing the war.

Most of the remaining fighters are in the rural desert areas around Dayr Az Zawr in Syria to the southeast of Raqqa, and Iraq's Anbar province, officials say.

Almost 8 million people lived under Islamic State group rule during its height. Five million have been liberated in the past year with 2.7 million Iraqis returning to their homes, McGurk said Thursday.

The air coalition, comprised largely of U.S. bombers, fighter jets, helicopters and drones and supported by artillery on the ground, conducted 11,400 airstrikes since Jan. 1.

That conflict has not been without its costs.The Associated Press reported this week that as many as 11,000 civilians died in the campaign to retake Mosul, roughly 10 times higher than previous assessments.

Yemen

The Islamic State group presence in the war-torn Arabian Peninsula nation, while small, has doubled in size this year, part of a larger trend of fighters and leaders fleeing the onslaught in Iraq and Syria.

"As ISIS is getting handed a defeat in other areas, they tend to try to push into areas of ungoverned spaces," says Army Lt. Col. Earl Brown, a spokesman for U.S. Central Command. "Those areas in the Arabian Peninsula, most notably in Yemen, have been some of those spots."

There are between 300 and 500 Islamic State group fighters in the area, mostly in Yemen but not limited to there. They're exploiting areas that are traditionally ungoverned or where governance has collapsed as a result of the ongoing war between Houthi rebels backed by Iran and forces loyal to the government currently in exile in Saudi Arabia.

The Islamic State group has also successfully recruited fighters formally loyal to al-Qaida in the Arabian Peninsula who have grown disaffected with a group that, while still among the most dangerous in the world, has suffered intense losses in leadership amid an ongoing U.S.-led commando and air campaign. Three AQAP leaders were killed in airstrikes on Nov. 2 and Nov. 20, according to Central Command, which oversees operations in the region.

Defense officials say the quiet U.S. mission to root out Islamic State group and al-Qaida fighters in Yemen exists in coordination with the exiled government.

Africa

The death of four American soldiers on a special operations patrol in Niger in October drew widespread attention to the intensifying covert war against extremists throughout the African continent, almost four times larger than the continental U.S.

The Islamic State group first expand its presence into Africa in Somalia in 2015 and conducted its first suicide attack in Bosasso in May. U.S. Africa Command estimates there are fewer than 250 fighters there, though they are able to conduct small-scale operations in the northern reaches of the country. A shadowy American targeting cell exists in Somalia to help coordinate counterterror operations outside of the capital, Mogadishu.

Islamic State group operativesentered the continent en masse in 2016 in Libya, whereas many as 8,000 fought to establish a foothold in the coastal city of Sirte to serve as a lifeboat amid steady losses in Iraq and Syria. A U.S.-led mission of airstrikes and special operations forces helped win back the city earlier this year, but not without scattering some of those fighters to other corners of the fractionated and war-torn country.

Now roughly 500 Islamic State group fighters are in Libya, though that assessment fluctuates, officials with Africa Command say. The group's presence there continues to be a focus of U.S. attention as it still poses a threat in planning attacks against Europe and Western interests in North Africa, officials say.

In 2015, the Islamic State group scored a propaganda win when Boko Haram, the Nigerian hard-line extremist group, declared itself an affiliate branch. The group fractured in 2016 when some fighters split to join the Islamic State group instead of remaining loyal to their own leaders.

This new branch, dubbed ISIS-West Africa, poses a more significant threat than Boko Haram, Africa Command officials say, due to its increased capability to plan and launch attacks. It was responsible for the attack on the convoy in Niger in July that killed at least 70 people.

The Islamic State group continues to operate in the Greater Sahara region, largely at the border of Niger and Mali, though that comprises a relatively smaller number of troops.

The Pacific Rim

Navy Adm. Harry Harris, chief of U.S. Pacific Command, said in October that it has witnessed terrorism and attacks inspired by the Islamic State group in Malaysia, Bangladesh and the Philippines.

"As we succeed in degrading ISIS in Iraq, Syria and Libya, radicalized, weaponized and displaced terrorists will seek new footholds in the Indo-Asia-Pacific," Harris said in a speech in Singapore at the time.

In 2016, the commander of the Islamic extremist group Abu Sayyaf based in the southern Philippine region of Mindanao, Isnilon Hapilon, was named the Islamic State group emir for Southeast Asia. Philippine forces, currently leading operations against the extremist network there, killed him in October during a campaign to retake the city of Marawi, though Harris said the leader's following represented an ongoing threat to the region.

"It's important to understand Hapilon's rise in 2016, when in just a matter of months he started uniting elements of several violent extremist organizations – building a coalition under the ISIS black flag," Harris said. "Today, Marawi is a wake-up call and a rallying cry for every nation in the Indo-Asia-Pacific. Foreign fighters are passing their ideology, resources and methods to local, home-grown, next-generation radicals. So we must stop ISIS at the front end and not at the back end when the threat can become even more dangerous."

When asked for specific numbers of ISIS fighters or operatives in the region, U.S. Pacific Command declined to comment.

"We do not comment on intelligence matters for security reasons," says Navy Cmdr. Dave Benham, a spokesman for the command.

The Caribbean

Then-Marine Gen. John Kelly, when he was still commander of U.S. Southern Command,first observed in March 2015 that people from Caribbean countries like Suriname, Venezuela, Jamaica, and Trinidad and Tobago had traveled to Syria or Iraq to join the Islamic State group, where "they get good at killing and pick up some job skills," like working with explosives. As many as 100 had returned to their homelands, which were largely devoid of intelligence or law enforcement infrastructure to hunt them down on their own.

In January 2016, Kelly, now White House chief of staff, observed that the Islamic State group's presence in the regionwas on the rise at a time when the Islamic State group was encouraging its followers to stay away from Iraq and Syria and plot attacks at home instead.

"It seems like the Islamic extremists and terrorists have shifted a lot of their message," Kelly told reporters at the time. "'Why don't you just stay at home and do aSan Bernardino or doBoston or doFort Hood?'"

Southern Command did not immediately respond to requests for comment on the current status of the Islamic State group in the Caribbean. Reports persist, however, thatlocal Muslims find inspiration in the Islamic State group and that it continues totarget tourists in the region, prompting warnings from those governments.