The bank said it "assumed" there would be economic red lines, like oil at $100 a barrel, that the US would be unwilling the cross.
The bank said it assumed at the start of the conflict that there would be "economic red lines" that the Trump administration would be unwilling the cross, and therefore it believed a deal would have been struck to open up the Strait of Hormuz shipping lane back in June.
It said such red lines included oil prices rising above $100 a barrel, inflation reaching 4%, gasoline topping $5 a gallon and rates on 10-year government borrowing hitting 5%.
JP Morgan is a huge name in the financial world, so for the investment bank to admit its experts are grappling with working out the economic impact of the US-Iran conflict reflects the tricky nature of trying to predict President Donald Trump's next moves.
An oil and gas industry source told the BBC it was "unusual" for such a high-profile investment firm to issue such a note, but added it was a "reflection on the state of play", given the uncertainties around the conflict.
Investors often make investment decisions on inflation expectations and the price of oil is a major factor in prices rising across the world, given the commodity's widespread use and humanity's dependence on it.
While gasoline remains below $5 and inflation has also not reached 4%, oil prices have surged back above $100 in recent weeks and the interest rate - known as a yield - on government bonds, which are issued in order for the US to borrow money from financial markets, has ticked over 5%.
"Six months later [since the war began], many of those lines have been crossed, yet the exit strategy is less clear, not more," said the commodities research team at JP Morgan in note.
"For the first time since the start of the Iran conflict, we don't have a baseline view. We simply don't know how to model the endgame."
How Trump and the oil markets move in sync: A tango in five charts
US borrowing costs hit fresh highs over inflation fears
US President Donald Trump said last week he did not think the Iran war would end until after November's midterm elections in the US.
"Right after the election, oil prices are going to be tumbling downward," Trump told reporters last week. "I think it's going to take a little bit longer than the midterm."
High oil prices have been behind the rising cost of living in the US and around the world, with fuel and energy prices surging ahead of the colder months.
The US central bank, the Federal Reserve, raised interest rates this week for the first time in more than three years and signaled they could be increased further this year and into 2027 in an effort to slow rising prices.
Fed Chair Kevin Warsh said the move was because "inflation is too high and has been for too long", though Trump disagreed with the decision.
Reporting synthesized and verified under Nexvoro.tech editorial guidelines. Full primary records referenced via BBC Business.
OpenAI has formed a new independent mathematics advisory group hosted at the Institute for Advanced Study in Princeton following a surge in automated problem-solving. The move arrives amid mounting academic scrutiny regarding the rapid pace of artificial intelligence in advanced mathematical research.
As debate intensifies over the rapid acceleration of artificial intelligence, OpenAI has proposed a comprehensive framework for international safety standards, focusing heavily on alignment research and recursive self-improvement. The move follows recent high-profile departures and escalating concerns from industry insiders regarding humanity's long-term control over advanced frontier models.
As Washington fiercely debates artificial intelligence oversight, Nvidia CEO Jensen Huang has emerged as President Donald Trump's top confidant, successfully pushing back against growing regulatory pressures. While rival tech executives advocate for government slowdowns, the head of the world's most valuable chipmaker is charting a rapid course for American tech supremacy.
