Current and former US officials say US forces are not positioned for a major, sustained Middle East conflict and the Pentagon may have to revisit assumptions about military needs in the region if the crisis deepens.
"I don't think we have all the forces that we would want to support Israel if there was a direct war between them and Iran," said Michael Mulroy, a former deputy assistant secretary of defense for the Middle East under the Trump administration.
Though Tehran has indicated it had no plans to retaliate for an apparent Israeli strike on Friday, the tit-for-tat attacks have raised fears of an unpredictable regional war that the United States has sought to prevent.
In the months since an attack by Hamas militants on Israel triggered a war in Gaza that has ignited unrest throughout the Middle East. The United States has rushed thousands of US service members to a region that had seen a steadily declining US presence over years.
Many of those new US troops are on warships and aircraft that move in and out of the region, and are only temporarily deployed. That US strategy to rely on surge forces could be tested now Iran and Israel have broken the taboo of open military strikes against each other.
"What it means for the US military is that I think we have to revisit this idea of what are the necessary, sustainable military capabilities that we have to maintain in the region," said Joseph Votel, a retired four star Army general who led US troops in the Middle East.
Votel and other former officials said the US military's success in downing Iran's drones and missiles last Saturday was presumably aided by detailed US intelligence that allowed the Pentagon to anticipate the timing and targets of Iran's attack.
"I think the bigger concern is our ability to be responsive over a sustained period of time," Votel said.
US officials say Iran does not appear to want an all-out war with Israel, and Tehran has played down Friday's strike. Still, experts warn the situation is unpredictable, particularly as long as the Israel-Hamas conflict rages.
US Army General Michael "Erik" Kurilla, the current head of Central Command, told lawmakers last month that he had requested more troops than the Pentagon had sent to his region, which President Joe Biden's administration has said is a lower priority than the challenge from China.
In written testimony to the House Armed Services Committee, Kurilla said a dangerous shortfall in US intelligence assets, targeting expertise and linguists contributes to gaps and seams in our ability to detect and disrupt plots, increasing freedom of movement for violent extremist organizations.
Although Kurilla's comments appeared more focused on Afghanistan, some intelligence shortfalls have already affected US strategy since the start of the war in Gaza.
For example, a lack of detail about Houthi weapons stockpiles before the Iran-backed group started attacking commercial shipping in the Red Sea has made it hard to determine the effect of months of strikes on the group's arsenal of missiles and drones, said officials.
Still, sending more US troops to the Middle East and bolstering intelligence assets longer-term could prove difficult, officials say.
"Troops are spread around Europe and those that aren't are going through overdue maintenance cycles," one US official said, speaking on condition of anonymity.
"And Asia is supposed to be the focus."
Another official said it was still unclear whether the US military was prepared to pull forces from Asia or Europe, despite the increase in tensions.
Prior to October, the last time the United States surged thousands of troops into the Middle East was under former President Donald Trump, during a series of escalatory actions that culminated in the US killing of Iran's top general and a retaliatory missile attack by Tehran on a US base in Iraq.
The first US official noted that the surge of troops in 2019 and 2020 was possible because, unlike today, Washington did not have to dedicate so many personnel and resources to Europe, a new reality following Russia's 2022 invasion of Ukraine.
Mulroy said the United States should strengthen its position in the Middle East without abandoning its China-first focus.
