Is Iran prepared to take the plunge?

"Iranian Major-General Qassem Soleimani, head of the elite Quds Force, and Iraqi militia commander Abu Mahdi al-Muhandis were killed early on Friday in an air strike on their convoy at Baghdad airport, an Iraqi militia spokesman told Reuters." This confrontation started when, "A US civilian contractor was killed and several service members and Iraqi personnel injured Friday in a rocket attack on a base in Iraq, military officials said." The US blamed the rocket attack on an Iranian backed militia Kataib Hezbollah. "US airstrikes targeted at least five locations of the Iraqi-based militia Kataib Hezbollah. The Pentagon says three targets were in Iraq and two in Syria. Kataib Hezbollah is closely linked to Iran's Islamic Revolutionary Guard Corps." At least 25 militia were killed in the strikes. Following the airstrikes hundreds of protesters attacked the US embassy in the highly fortified Green Zone in Baghdad. Protesters burned a guard room and damaged property before withdrawing. Attack on the embassy would have been taken very seriously by the US establishment because the US has not forgotten the attack on the US embassy in Tehran in 1979 when over 60 Americans were taken hostage by Iranian students. President Jimmy Carter lost his re-election to Ronald Reagan by a landslide in 1980. President Donald Trump warned Iran of serious consequences for attacking the embassy to which Iran's Supreme Leader Ayatollah Khamenei taunted that the US "can't do anything". Khamenei may have been assured by Trump's reluctance to risk lives of US soldiers in an all out war with Iran. In June, Iran shot down a US drone but Trump decided not to retaliate so as not to inflict casualties. In September, Houthi rebels in Yemen, backed by Iran, claimed a large scale drone attack on two refineries in Saudi Arabia. The US blamed Iran which denied responsibility. "I'm somebody that would like not to have war," said Trump after the attack. The attack on the embassy in Baghdad may have been an insult too far for Trump. With its economy collapsing under sanctions imposed by Trump, Iran unveiled a "budget of resistance" in December. In November, protests broke out at 719 locations against a hike in the price of fuel, wrote Saeed Ghasseminejad. Over 1,000 protesters were killed by the government. In October, Soleimani "instructed his top ally in Iraq Abu Mahdi al-Muhandis, and other powerful militia leaders to step up attacks on US targets in the country using sophisticated weapons provided by Iran". Although Soleimani has been a target of the US for decades past presidents were too scared to take him out so he must have thought that he is immortal. "He (Soleimani) said, 'Gen Petreaus, you should know that I, Qassem Soleimani, control the policy of Iran with respect to Iraq, Lebanon, Gaza and Afghanistan,' Petreaus said." So he came into Iraq as though he owns it. No more. Iran has vowed "harsh retaliation" against the US. Is Iran prepared for an all out war with the US, which will surely be supported by Israel and Saudi Arabia? Or is it just talk?