The deadly American raids in Iraq and Syria on Kataib Hezbollah, An Iran-backed militia could become a critical point of confrontation between Tehran and Washington that takes place in Iraqi territory, analysts told Al Jazeera.
On Sunday, the United States carried out air strikes against three of the group's bases in Iraq and two in Syria, killing at least 25 suspected members of the group.
US airstrikes followed a rocket attack on Friday near Kirkuk, which the United States blamed on Hezbollah, in which an American civilian contractor died and four members of the US service were injured along with two members of the Iraqi security forces.
Iran criticized the US air strikes against its allied militias in Iraq and Syria, saying that the United States "showed its support for terrorism."
Iraq condemned the US attack as a "violation of Iraqi sovereignty."
In a statement on Sunday, the Iraqi provisional prime minister, Adel Abdul Mahdi, called the measure "a dangerous escalation that threatens the security of Iraq and the region."
Unlike other Iraqi militias backed by Iran, such as the Hashd Alabama-Shaabi Kataib Hezbollah, which has formal legal and military ties with the Iraqi army, is directly controlled by the military and religious leaders of Iran, according to Muhanad Seloom, an expert in Iraq and assistant professor of critical security studies at the Graduate Studies Institute of Doha in Qatar.
"The latest violence between the US-backed militias and Iran in Iraq signals a serious escalation," said Seloom.
While Washington and Tehran are locked in various political and military confrontations in the region, especially in the Gulf and Yemen, Friday's attack, allegedly by Kataib Hezbollah, could be seen as an Iranian attempt to respond to the growing political and economic pressure exerted by the United States. , Seloom argued.
Tensions between the United States and Iran have increased since Washington withdrew from a historic nuclear agreement with Tehran last year and began imposing punitive sanctions.
The latest development also occurs amid growing public anger in Iraq against the political establishment, which protesters accuse of widespread corruption and being indebted to an "invasive,quot; Iranian influence.
However, Iran says the mass protests were instigated and supported by the United States to undermine its presence and interests in Iraq.
Iraqi security forces are accused of killing about 500 people since the beginning of the movement months ago.
After the US invasion in 2003 and the overthrow of President Saddam Hussein, Iraq has been ruled by parties with religious and financial ties with Iran.
"Iran will use its representatives of the Shiite militia in Iraq and other parts of the region to attack the forces and bases of the United States in order to fight the pressure of the United States against him in the region," Robert Baer , A former CIA intelligence officer who worked in Iraq for several years, told Al Jazeera.
Baer said he does not expect Tehran to step back against the United States, as he attempts to derail US policies that he believes are against the interests of the Islamic Republic.
"If the United States and Iran continue to fight in Iraq in this way, Iran could eventually resort to kidnapping American citizens in the region, in the same way that happened in Lebanon during the 1980s," Baer said. "Given the current political and military conditions in Iraq, the United States remains vulnerable there."
But Abas Aslani, principal investigator of the Center for Strategic Studies of the Middle East in Tehran, rejected the idea that Iran should be blamed for the latest military attack on the US base in Iraq.
Aslani argued that Iraqi groups act independently and do not follow Iranian commands.
"The Americans want to blame the Iranians for their failure in Iraq, especially after spending billions of dollars on their war efforts, but they ended up with Iran as the winner in Iraq," he said.
Aslani said the United States is eager to sabotage the Iran-Iraq relationship, because those two countries are on good terms.
US Admiral William Fallon, former head of the US military command in charge of Iraq and Afghanistan, told Al Jazeera that the latest incident was "another episode of an ongoing struggle,quot; between Iran and the United States.
Fallon said that although he does not believe that Washington or Tehran are interested in escalating the conflict to a higher level of confrontation, "it is not known where it will go if other factors come into play on the ground."
"But despite that … The United States is not retreating when facing Iran and its representatives in Iraq and Syria."
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