The killing of Qasem Soleimani, Iran's top general of the elite Quds Force of the Islamic Revolutionary Guard Corps, in a drone strike by the United States on Jan 3, will inevitably provoke retaliation from Iran.

The assassination has also enraged the Iranians. Soleimani was the key architect of Iran's regional influence, a national hero, a power broker of the Shiites, a military strategist in fighting terrorism and a confidant of Ayatollah Ali Khamenei, Iran's supreme leader, who fondly called him "a living martyr".

Soleimani's death will undermine Iran's regional influence. His Quds Force focuses on overseas operations like collecting intelligence and developing and managing proxy militias. It has been a main vehicle for Iran to cultivate Shiite militias in the Middle East.

For instance, Iran has been backing and funding overseas anti-American and anti-Israeli forces, including Bashar Assad in Syria, Hezbollah in Lebanon, Houthi in Yemen and Popular Mobilization Forces in Iraq. Sometimes, it has even orchestrated their activities.

Killing the top brass of a nation is an act of aggression. The US has flagrantly violated international law by eliminating Soleimani, a move that could possibly trigger a war.

The US took out Soleimani amid the escalated US-Iran confrontation. The Pentagon has identified Iranian-backed Hezbollah militia as the culprit behind the Dec 29 attack on a US facility in the Iraqi city of Kirkuk that killed a US contractor. In retaliation, the US launched airstrikes on three Iran-backed militia bases in Iraq and Syria, killing 25 militia fighters and injuring 50.

The attacks sparked a wave of protests in Iraq. On Dec 31, thousands of Iraqis stormed the US embassy and vandalized property. The US suspects Teheran's role in the embassy siege.

Amid the growing US-Iran conflict, the killing of Soleimani has served two purposes. First, it has sent a strong message to Iran. Second, it has curtailed the regional clout of Iran. The killing also sends a warning to Iraq, which is a close ally of Iran. The US believes that without a mastermind like Soleimani, Teheran cannot hold sway over the region as it used to.

The order to kill Soleimani was spurred on by Iran hawks in the US administration. The US and Iran have been on a near collision course for years, but both sides are aware of the high price of a war. That is why the previous administrations in the US, led by George W. Bush and Barack Obama, resorted to isolation, sanctions and embargoes, and any US-Iran military confrontation has been limited to proxy wars.

Trump has been withdrawing from the hot spots of Syria, Iraq and Afghanistan. Maybe this time he heeded counseling by his advisers to execute Soleimani, who had many Americans' blood on his hands and was plotting another attack against the US. Killing him was a preemptive move, according to some US officials.

Iran will seek revenge because it needs to show a hard stance to the international community and the aggrieved Iranians. The killing of Soleimani will give Iran a rational cause to go to war with the US. In addition, it could plunge the entire Middle East into a war.

While the US has unrivaled military strength, Iran has unique geopolitical advantages in asymmetric warfare. Pro-Iran forces in Lebanon, Syria, Yemen, Iraq and Palestine can pose a serious threat to the US military bases and diplomatic agencies in the Middle East, as well as to Israel.

Zou Zhibo is vice-director of the Institute of World Economics and Politics of the Chinese Academy of Social Sciences. The views do not necessarily reflect those of China Daily.