US Secretary of Defence Lloyd Austin observes the national anthem during a ceremonial welcome at the Defence Ministry in Seoul on January 31, 2023. Photo: AFP

Pentagon chief Lloyd Austin has received harsh criticism in recent days for leaving the US President Joe Biden, the White House, and even his Department of Defense (DOD) colleagues in the dark for days about his hospitalization, at a time when the US faces a slew of complications overseas, with the growing risk of conflict spillover in the Middle East and a prolonged battle in Ukraine. 

Austin's unannounced absence from office reflected the chaotic management of the US government, and has provided Republicans with fresh ammunition to attack the Biden administration before the upcoming presidential election, experts said.

According to a CNN report citing sources familiar with the matter, the head of DOD was admitted to a hospital's intensive care unit on New Year's Day due to complications from an elective surgery, but Biden was not informed about the matter until four days later on January 4, when national security adviser Jake Sullivan told him.

It came as a shock to all White House staff as the Pentagon didn't make the information public until Friday evening, notifying Congress only 15 minutes before releasing a public statement.

The news came as a surprise to even Pentagon staff. Deputy Secretary of Defense Kathleen Hicks, who was told to assume some of Austin's responsibilities on January 2 while still on vacation in Puerto Rico, did not know the true situation until January 4, officials revealed. 

As the highest-ranking leader in the DOD and the principal advisor to the US president, the secretary of defense plays a crucial role in both the administrative and operational command chains of the military. 

And due to the suddenness, fast pace, and high intensity of modern warfare, the efficiency of command and control directly affects the operation of war. Under these circumstances, Austin's multi-day absence was met with outrage in military and political circles, Chinese analysts said.

"This should not have happened this way," said one of US official. Others from the GOP called the event a "shocking breakdown," pointing out that Austin's position requires the weightiest of decisions to be made in minutes, including "the nuclear chain of command."

The event reflected a disorderly US government with both the DOD and the Biden administration neglecting their duties, Li Haidong, a professor at the China Foreign Affairs University, told the Global Times on Monday. "As the president, Biden has proven to be inadequate in knowing even the whereabouts of his cabinet members," the expert said. 

The main reason for Austin's silence is likely to be personal, analysts said. For one thing, Austin has always impressed others as a relatively low-key figure who stresses privacy. Another reason may be that he wanted to avoid causing disruptions to the actions of the US military due to personal health issues, they noted. 

While Austin remains in hospital, the US government is drawing up a number of plans to respond to mounting concerns that the war in Gaza could expand into a wider, protracted regional conflict.

Austin, who resumed his responsibilities as defense secretary Friday night, remained hospitalized Sunday, according to the Wall Street Journal.

There has been no disclosure as to whether Austin lost consciousness before or after being admitted to the hospital, nor has it revealed to what extent his responsibilities were handled by his deputy.

As the two most prominent candidates for the election - the incumbent and the former president Donald Trump - began their campaign rallies, the DOD chief's mishap dealt a heavy blow to Democrats, as it offered Republicans new ammunition with which to attack Biden and add fuel to the fire, by criticizing his incompetence not only in governing the country but also his own cabinet, Li said.