With the US presidential election fast approaching, we take a look at what a Democratic win could mean for the US oil and gas industry. We have analysed four possible scenarios of increasing severity to fully assess the ramifications from Joe Biden's promise to ban “new oil and gas permitting on public lands and waters”. The impact could be enormous. At the least restrictive end, we estimate a ban on new exploration lease sales would result in over 6 billion boe of prospective resources lost, over US$75 billion of capex not spent, and government revenues close to US$50 billion lighter. At the most extreme end of the scale, a total ban on future production from public lands and waters, would lead to over 25 billion boe of resources left in the ground. In the GoM, this would be catastrophic with production of over 2 million boe/d shut in and several operators put out of business. In Alaska, hopes of reversing the past trend of decades of production decline would be destroyed.