US President Barack Obama, who had pledged not to interfere in other countries' affairs, authorized US military on Friday to carry out "targeted air strikes" against extremists in Iraq. His decision can be seen as a response to compelling situations in the Middle East.

Tens of thousands of people, many of whom are members of the Yazidi (Kurdish) community, are trapped in the Sinjar mountain area by Islamic State of Iraq and the Levant extremists. And given the ISIL's record of belligerence and cruelty, it is feared that the Yazidis could be massacred.

Worse, ISIL forces could enter Erbil, capital of the Kurdish autonomous region of Iraq, where Americans man several US agencies. Even if the ISIL fail to seize the city, their members could enter it in small groups and launch attacks, threatening US citizens' lives and causing grave political reactions in the US.

Such fears left Obama no choice but to react to the challenge of the ISIL. However, Obama has to face domestic opposition to military intervention in other countries, which is now fierce if the country is in the Middle East. The presence of US citizens in Erbil prompted Obama to order the air strikes without much opposition, and his response could save not only American citizens but also Iraqi civilians.

The result of the air strikes is not difficult to guess. The ISIL relies mainly on ground weapons, like heavy machine guns carried on trucks, to expand its area of influence. Ground forces without ample anti-aircraft firepower, like the ISIL, are easy targets for the US Air Force. In fact, the air strikes launched by Syria against extremist forces in Iraq in June proved quite effective.

But US military aircraft may have to stay longer in bases near Baghdad because no one can be sure when the operation will end. The Iraqi military has proved vulnerable against the ISIL, so it cannot defeat the extremist forces without the help of US ground forces.

In a sense, authorizing targeted air strikes in Iraq is another testimony of the failure of the US' Iraq policy - the first being the growth of the ISIL as a powerful force. The US overthrew what it calls tyranny in Iraq to introduce Western-style democracy, but not enough people support this form of government to even defend the country.

That has been the problem with US intervention in the Middle East, because Washington never understood the difference between overthrowing "undemocratic" regimes and fighting terrorism and extremism. By overthrowing a "non-democratic" government with the help of guns in the Middle East, the US has opened a Pandora's box of Islamic extremism, which is threatening local people as well as the US.

American politicians are becoming increasingly wary of intervening militarily in other countries to change regimes. Let's hope they learn a lesson from the mess they have created in Iraq and refrain from repeating the mistake.

The author is a researcher in Middle East affairs at the Chinese Academy of Social Sciences.