The debate emerged after Iran launched missiles at Israel following Israeli strikes in Beirut's southern suburbs, at a time when negotiations between Tehran and Washington were widely described as nearing an agreement.
Although Iran's Khatam al-Anbiya Central Headquarters announced on Monday that it was halting further strikes, it warned that attacks would resume if Israel targeted either Iran or Lebanon again.
US President Donald Trump called on both sides to halt retaliatory attacks, while Foreign Ministry spokesman Esmail Baghaei said Washington bore "direct responsibility" for any action taken by Israel against Iran.
Speaking to the Revolutionary Guards (IRGC)-linked Tasnim News Agency, an unnamed military source dismissed Washington's lack of public endorsement for Israeli attacks as a "purely propagandistic and deceptive act."
"If the Israelis and Americans believe they can, through 'controlled escalation,' make Iran and the Resistance Front predictable or limit the nature of Iran's response, they are making a foolish mistake," he said.
A new strategic doctrine?
Among the most notable reactions came from Sadegh Larijani, chairman of Iran's Expediency Council.
In a post on X, Larijani described the strike carried out in defense of Lebanon as "the official declaration of a strategic doctrine" and the opening of "a new chapter in defense policy," in which Iran would pursue its regional power through initiative and offensive capability.
Parliament Speaker Mohammad Bagher Ghalibaf, who also heads Iran's negotiating team in talks with Washington, argued that Iran had "overturned the equation of a ceasefire on paper and its repeated violation on the battlefield."
"As long as there is no genuine will for confidence-building, Iran's response will remain the same," he wrote on X.
President Masoud Pezeshkian struck a more measured tone, arguing that diplomacy and deterrence remained complementary rather than contradictory.
"We will firmly defend the rights of the nation and retreat before no threat," he wrote. "Diplomacy and defense are the two wings of national power; we have abandoned neither the battlefield nor the negotiating table."
Media echo the new strategy
Iranian media quickly expanded on that interpretation, arguing that the strike reflected a broader shift in Tehran's deterrence strategy.
Farda News, a website close to Ghalibaf, argued that attacks on Lebanon would no longer be cost-free and that Israeli actions on one front could trigger responses on another. The outlet also interpreted the reported targeting of the Haifa refinery—described by the IRGC as retaliation for attacks on Iran's petrochemical industry—as an example of "strategic symmetry."
"The era of cost-free attacks on the Resistance Front has ended," it wrote.
Other conservative outlets advanced similar arguments. Tabnak, which is considered close to Mohsen Rezaei, an adviser to Iran's supreme leader, argued that Tehran had for the first time retaliated militarily for an Israeli attack on a country other than Iran itself.
Khabar Online described the strike as a redefinition of deterrence equations in the Middle East, while Rouydad24 argued that Tehran was signalling a willingness to expand both the geography and scope of future confrontations.
Several commentators framed the issue not simply as support for Hezbollah but as a test of Iran's credibility with its regional allies. Allowing Hezbollah to be weakened or destroyed without a response, they argued, would undermine decades of Iranian regional strategy and raise questions about the reliability of Tehran's support for its partners.
Mixed reactions online
Public reactions on social media were more divided.
Some users criticized Iran's involvement on behalf of Hezbollah. One commenter wrote that Iran had effectively become "the proxy force of a foreign group called Hezbollah," arguing that resources intended to strengthen Iran's own security were instead being spent defending an ally.
Others focused on the domestic costs of escalation.
"If they hit our water, electricity, refineries and power plants tomorrow, remember that your Revolutionary Guard brothers dragged Iran into war because of Lebanon," one user wrote.
Several users expressed concern that prolonged conflict could make Iran resemble Lebanon, a country long marked by instability and recurring wars.
"I fear the Beirutization of Tehran," one commenter wrote. "I am terrified of the Beirutization of Iran."
Together, the reactions highlighted a widening debate over the costs and benefits of Tehran's regional strategy. While officials and conservative media presented the strike as the emergence of a new deterrence doctrine, many ordinary Iranians appeared more concerned about the risks that such a doctrine could bring at home.
