While journalists had access to detailed, often-daily briefings as well as embeds with troops during previous wars such as those in Iraq and Afghanistan, the US military has taken a markedly different approach to communicating during the Iran conflict.

"The Pentagon is putting out less information less frequently than ever, and the information that they are putting out is... less informative," said Steve Warren, a retired US Army colonel with 20 years of public affairs experience.

He noted that during Iraq, Afghanistan and the war against the Islamic State group, the US military held frequent briefings and had "a dedicated communications cell that was empowered to live by the sort of tenet of maximum disclosure with minimum delay."

That has not always been the case during the current conflict, with key questions such as whether the United States was responsible for a deadly strike on an Iranian elementary school and Washington's post-war plans for Iran continuing to go unanswered.

Pentagon Press Secretary Kingsley Wilson said in response to a request for comment that "the media has received an overwhelming amount of information from the Pentagon whether they'd like to admit it or not."

She cited five press briefings held since the start of the war on February 28, video updates from US Central Command (CENTCOM) leader Admiral Brad Cooper, and widely viewed posts on social media accounts from that command and the Pentagon.

While top officials gave briefings during previous conflicts, Defense Secretary Pete Hegseth, top US officer General Dan Caine, and CENTCOM's Cooper are the only ones who have done so from the US military during the current war.

"There is no precedent for that in my knowledge," Warren said, referring to the top officials being the only ones to brief reporters.

Asked why it is important for the Pentagon to provide information to the media and the public, Warren said the military needs to explain "how we are spending the...nearly $1 trillion we've been entrusted of national treasure, and what we are doing with America's sons and daughters."

"I've always felt like it's a moral imperative, it's a duty to explain how we're spending the money and what we're doing with the people," he said.

- 'Completely opaque' -

Hegseth has devoted portions of several media briefings to attacking the way the "fake news" has covered the conflict, especially taking aim at broadcaster CNN.

On Friday, the former Fox News host was particularly incensed by a story the channel ran suggesting Washington had underestimated Iran's ability to disrupt global oil traffic in the Strait of Hormuz.

"Patently ridiculous," Hegseth told reporters, before saying he looked forward to an ally of President Donald Trump taking over the network.

The Pentagon's restrictive approach to the media predates the current conflict and began after Trump took office for a second term last year.

Trump administration officials curbed the media's ability to move around the building, forced some outlets to vacate offices there and drastically reduced the number of briefings for journalists.

News outlets were later told they had to sign a more restrictive media policy in order to maintain access. Almost all refused, and were required to hand in their Pentagon credentials.

More recent limits have followed, including restricting news photographers from briefings -- reportedly after Hegseth's staff objected to the way he looked in news photos.

"We have far fewer real journalists in proximity to the Pentagon, which is a major transparency problem," said Roger Stahl, professor of communication studies at the University of Georgia.

That means "unsavory facts will take longer to come to light, if they do at all. The administration will feel less pressure to provide a coherent justification and plan," he said.

Stahl said that on Iran, "the Trump administration has been completely opaque."

It is the "first major operation where the executive branch doesn't even bother to make the case to Congress and the American public. And it has made no real attempt in the aftermath of the strikes to provide a coherent justification," he said.