President Trump faces a momentous decision on a tight timeline: carry out his threat to obliterate Iran's infrastructure beginning at 8pm ET, or push his own deadline again to give negotiations a chance.Why it matters: Trump has threatened to destroy every bridge and power plant in Iran by midnight, among other options that would have devastating consequences for ordinary Iranians and spark dangerous retaliation across the region.Mediators from Pakistan, Egypt and Turkey are working to avert that outcome by brokering a deal — or at least putting time back on the clock."If the president sees a deal is coming together, he'll probably hold off. But only he and he alone makes that decision," a senior administration official told Axios. A defense official said they were "skeptical" there would be any extension this time around.This account is based on interviews with six officials and sources with direct knowledge of the ongoing diplomacy or Trump's thinking.Behind the scenes: Trump might be the most hawkish person in the top echelons of his administration on Iran, according to a U.S. source who spoke to him several times in recent days. "The president is the most bloodthirsty, like a mad dog," another U.S. official said, downplaying stories that Defense Secretary Pete Hegseth or Secretary of State Marco Rubio were egging him on. "Those guys sound like the doves compared to the president."Trump has started sounding out advisers and confidants about the plan to strike power plants and bridges by asking them, "What do you think of Infrastructure Day?"Breaking it down: Trump's negotiating team —Vice President Vance, Steve Witkoff and Jared Kushner — thinks he should try to get a deal now if possible.Meanwhile, Israeli Prime Minister Benjamin Netanyahu, the leaders of Saudi Arabia and the UAE, and political allies like Sen. Lindsey Graham (R-S.C.) are urging Trump not to agree to a ceasefire unless Iran makes concessions that currently appear unlikely, like reopening the Strait of Hormuz or relinquishing all highly enriched uranium.The other side: Iran gave a 10-point response to the current peace proposals on Monday. A U.S. official described it as "maximalist," but the White House saw it as a negotiating gambit, not a rejection.The mediators told the White House they're working with the Iranians on amendments and redrafting.They also cautioned that Iranian decision-making is very slow, so an extension of the deadline might be needed.Between the lines: Trump suggested the phlegmatic pace of Iranian deliberations was holding back the talks during his press conference on Monday, noting that Iranian leaders can't communicate efficiently due to security concerns. He said Iranian leaders had to use children to pass notes back and forth. One source said Trump was alluding to the means by which Supreme Leader Mojtaba Khamenei has been communicating with the outside world and giving orders to his subordinates.Trump's advisers told the mediators the president needs to see positive indications from the Iranians to consider an extension. "We're knee-deep in negotiations, anything can happen," one said.What he's saying: Trump laid out a dire vision of Iran's near future during his press conference, while adding that a deal was still possible."The entire country could be taken out in one night, and it might be tomorrow night," Trump said."We have a plan where every bridge in Iran will be decimated by 12 o'clock tomorrow night. Where every power plant in Iran will be out of business, burning, exploding and never to be used again. I mean complete demolition by 12 o'clock, and it will happen over a period of four hours if we wanted to," Trump said. "We don't want that to happen."On the other hand, Trump said negotiations were "going fine" and stressed the U.S. has "an active, willing participant on the other side" that is "negotiating in good faith."What to watch: Two sources said a plan for a massive U.S.-Israeli bombing campaign against Iran's energy facilities is ready to go, if Trump gives the order."Trump would take a deal if he got one, but it's unclear if the Iranians are ready. It will be extremely tense until Tuesday at 8pm," a U.S. source close to Trump said.