Andrew Walker, Oxfordshire assistant deputy coroner, recorded a narrative verdict on Cpl Stephen Allbutt's death.
He did not record an "unlawful killing" verdict because the 35-year-old, from Stoke-on-Trent, Staffs, died in combat.
Trooper David Clarke, 19, of Littleworth, Staffs, also died but his body has never been found.
The inquest heard that the pair, who were serving with the Queen's Royal Lancers, had been fired on by a British Black Watch tank crew.
They died just five days after the start of the Iraq war, near Basra, on 25 March 2003.
After the inquest, the Ministry of Defence apologised to the families of Cpl Allbutt and Trooper Clarke.
It said it would consider Mr Walker's findings to see if any further action was needed.
Mr Walker said that Lt Col Lindsay MacDuff, who was a major commanding B Company, 1 Black Watch, at the time had "failed to appreciate" the danger the men were in when discussing platoon positions with the tank troop commander.
Lt Col MacDuff had earlier told the inquest he had told his men about the presence of two nearby "friendly" tanks, but they said they had not been given the message.
Mr Walker concluded on Thursday that there was "no evidence" that any message had been passed to the tank commander.
A crucial radio log had gone missing, he said.
Mr Walker criticised the gaps in communication between commanding officers and said Cpl Allbutt's death followed a "catalogue of misunderstandings and failures".
He said: "The centre of this tragedy represents a serious failing and it will fall to others to question the fitness of this officer (Lt Col MacDuff) to hold command."
Cpl Allbutt's widow Debie stood beside Daniel Twiddy, who was severely injured in the incident which killed her husband, as she made an emotional statement outside the coroner's court.
She called for Lt Col MacDuff, who has been promoted to command a regiment of the Black Watch, to be prosecuted and removed from his post.
"Maybe the mothers, fathers, husbands and wives of the soldiers in that regiment should question whether they want this man in charge. I wouldn't.
"I ask for this man's resignation," she said.
Mrs Allbutt described the Ministry of Defence as "completely unco-operative" and said delays in providing her with the documentary evidence relating to her husband's death meant that her team had "only three weeks to prepare for what has been described as the most important military inquest to take place in the UK".
She also called on the government to end the principle of "combat immunity", which appeared to prevent the coroner from recording an "unlawful killing" verdict.
Mr Twiddy, who is medically discharged, said: "I'm totally ashamed of the Ministry of Defence and I have got no respect at all for them."
Mrs Allbutt told the BBC that the MoD's apology was "not good enough" because it had been issued through the media and did not extend to the injured soldiers.
In its statement, the MoD said: "Regrettably, this tragic incident happened in the confused and dangerous environment that characterises war.
"We extend our thoughts and deepest sympathies to their families, friends and colleagues at this difficult time."
The statement also said its internal board of inquiry had identified failings that contributed to the incident and it made a number of recommendations all of which were being implemented.
Before Mr Walker gave his verdict, lawyers for the MoD indicated that they had not yet had sufficient time to consider whether any prosecutions could be made.
Güncelleme Tarihi: 12 Temmuz 2007, 19:26