Islamic State is by far the most barbaric terrorist group. Founded on the war-torn ruins of Iraq and Syria, the IS is reportedly using "sex slaves" and indiscriminately executing captured Iraqi soldiers. And it excels in uploading videos of hostage executions on the Internet to spread terror.

Worse, the IS' influence on disgruntled, misguided people seems to be increasing. The man who took 17 hostages in a café in Sydney, which resulted in three deaths and left four people injured, is believed to have been a sympathizer of the terrorist group.

The IS has imposed "Islamic rule" in the territory it controls in northern Iraq while its leaders dream of conquering the entire Islamic world and even "raising the flag of Allah in the White House".

How did such an extremist group emerge in the 2010s? The root cause is the complicated geopolitics of the Middle East, which has rarely seen peace after World War II. Chaos in the region has bred extremism and terrorism, which, in turn, create more chaos. It is a vicious circle.

The United States and other Western powers worsened the already grave situation in the Middle East by their frequent interventions in the region on the pretext of spreading democracy. The US has not only defined a "failed state", but also created two examples out of Afghanistan and Iraq with its "war on terror". Before the invasions, the US didn't realize that it would break the power balance that had suppressed terrorism in the region.

Having realized its mistakes, the US has formed an alliance with both European and Arabian powers against the IS. Within a year, the alliance has launched more than 600 bombings and air strikes against IS in Iraq, without sending any ground forces. Earlier this month, the US Senate approved an annual defense budget of $496 billion, of which $3.4 billion was earmarked for military action against the IS and $1.6 billion to provide training to Kurd forces to fight the Islamic extremists.

The IS may not succeed, partly because of the US' strikes and partly because its policies are against humankind in general. History has not been kind to autocrats and religious bigots as rulers.

But the IS' failure does not mean a victory for the US. As the only superpower, the US could easily overthrow Saddam Hussein and annihilate Osama bin-Laden, but it can neither reshape the Iraqi civilization according to its so-called democratic norms nor can it eliminate terrorist groups in Afghanistan.

Running for the US presidency, Barack Obama vowed to end the wars in Iraq and Afghanistan. Yet the IS has emerged during his rule to push the Middle East into an even deeper chaos. Even if the IS is defeated, the US will have to face more problems in the Middle East, whose political and social order has been turned upside down by Western interventions.

More than 6,000 US soldiers lost their lives in the 10 years' "war on terror", but their sacrifice hasn't earned the US more friends in the Middle East. In contrast, anti-Americanism has become even more rampant. After the Sept 11, 2001, attacks, the US media used to ask: "Why do they hate us?" That was a sign of profound thinking. But they should have listened to the most popular question in the Middle East: "Why do they (the US) hurt us?"

Democracy and prosperity are the future of human societies, but they cannot be realized overnight; only when peace and stability are established can they become reality. And without the establishment of peace and stability, it is impossible to eliminate terrorism from any place, let alone the Middle East. Hopefully, the US realizes this fact now. This is important, because the IS has caused the world enough damage and no one wants it to turn into a permanent threat to humankind.

The author is a researcher on Middle East Studies at the Chinese Academy of Social Sciences.