(Reuters) -- The death count from Tuesday's separate bombing attacks in Brussels continued to climb Wednesday, with Belgium police reporting at least 31 dead and nearly 270 injuried. The atrocities are tragic and unacceptable. But the West should understand that this is what winning may look like in the battle against Islamic State. The attackers' coordinated strikes could well stem more from a sense of weakness, than strength.
Islamic State has recently taken a series of serious hits at its power and prowess. First, and most important, its territory in Iraq and Syria - the "caliphate" that has attracted foreign fighters from around the globe - has been steadily diminishing in size over the past 15 months, and the territorial losses are escalating. Since January 2015, the militant group has lost an estimated 22 percent of its territory in Iraq and Syria - with 8 percent of those losses in 2016.
This past month, a cache of thousands of Islamic State documents was leaked to the European media. In Arabic, the documents consisted of Islamic State member forms, including such biographical information as names, ages, education, skills and whether or not the individuals were still alive.
Then, four days before the Brussels bombings, the supposed mastermind of the November Paris attacks, Salah Abdeslam was captured in the neighborhood where he grew up in Belgium. Authorities have announced that he is cooperating,with law enforcement presumably providing them with information about his network, its plans and potentially the names and plans of individuals who pose an imminent threat to the safe and security of Europe.
This combination of circumstances - severe territorial losses in Iraq and Syria, leaks of revealing documents and the capture of someone who likely knows the extent of the wider network and its future plans - may have pushed the Brussels cell to the point of panic. True, the network's plan had been laid out, its weapons amassed, its suicide bombers chosen. Yet the Brussels attacks may still have been a sign of a group feeling cornered and on the run.
One reason the West may be missing this point is that the Brussels bombings trigger fears associated with the now iconic details of previous al Qaeda attacks. The images of an internationally known target, with mass civilian casualties, multiple suicide bombers and the use of explosives - this is the al Qaeda playbook, which those who call themselves the Islamic State have now taken up.
The attacks on transportation systems in Brussels, the airport and the subways, recall the London bus and subway bombings in 2005 and the Madrid train station bombing in 2004 - which together resulted in hundreds of deaths. Pointedly, as an attack on a world-renowned international center, home of the North Atlantic Treaty Organization and the European Commission, where individuals of many different nationalities were destined to be among the victims, it is reminiscent of 9/11.
But there is a noteworthy difference between the earlier al Qaeda attacks and this Islamic State attack in Brussels. With 9/11, as well as in Madrid and London, al Qaeda was on the rise, waking up the world to its destructive capacity.
Osama bin Laden tried several times before 9/11 to get the attention of the United States - but failed. The coordinated bombings of the U.S. embassies in Kenya and Tanzania in 1998; the bombing of the USS Cole, a guided-missile destroyer, in 2000; and the bombing of the U.S. Air Force barracks at Khobar Towers in Saudi Arabia in 1996 - all were taken in stride, the concern largely of U.S. law-enforcement officials and journalists. The destruction of the World Trade Center on 9/11 changed all that.
Shortly before the Paris attacks, which claimed the lives of 137 people, President Barack Obama remarked on the West's successes against Islamic State in Syria and Iraq. Some analysts surmised, after the deadly attacks, that these territorial setbacks in the Middle East had frustrated Islamic State and led its members to turn to Europe as a more accessible venue for their portfolio of destruction.
Why does it matter whether this possible shift in focus is a sign of weakness or strength, of frustration or confidence? Because it provides insights into how the West should react to the Brussels attacks.
For starters, law enforcement - the front line of this asymmetrical war outside of the Levant - should do exactly what it has been doing: find the perpetrators, identify the members of their wider network and seize the weapons and the persons responsible for the bombing attacks.
But the larger question of fear is at issue here. If the Brussels attacks are indeed a desperate sign of panic on the part of Islamic State, then the proper response to Brussels is not fear, but a sense of sorrow and loss. We - the public, the media, public officials and politicians - would do well not to yield to the inaccurate and inflame our sense of vulnerability and weakness. The defensiveness of Islamic State on the run may well reap far more violence before the group's death throes. But the West should not be deterred from keeping up its pressure on Islamic State at home and abroad.
The realities of terrorism call for constant vigilance as a fact of life, and will for a long time to come. No more and no less.
（Written by Karen J. Greenberg)
*Karen J. Greenberg is the director of the Center on National Security at Fordham Law School, focusing on national security, terrorism and civil liberties. Her newest book, "Rogue Justice: The Making of the Security State," will be out in May. The opinions expressed here are her own.