The deaths cast doubt over Tokyo's plan to send more troops
The killing of two Japanese diplomats in an ambush near Tikrit on Saturday is the cause of much soul-searching in the media.
The deaths of Katsuhiko Oku and Masamori Inoue prompt some papers to ask whether government plans to dispatch Japanese Self Defence Force personnel to Iraq should now be scrapped.
And there is condemnation that the two envoys were not better protected.
"Why did the two head for Tikrit without accompanying security personnel?," The Daily Yomiuri questions, urging the Foreign Ministry to "investigate the reasons behind this latest attack and whether information gathering and security measures were adequate".
Describing their deaths as "a heartrending sacrifice", it nevertheless urges Tokyo to stay the course in Iraq. "We should not flinch... Japan should act decisively to extend its support to post-war Iraq."
"Only by doing so can Japan carry out the wishes of the two diplomats, who died violent deaths with their work unfinished."
A leading news agency, Kyodo Clue II, also criticises "the government's lax, wishful outlook on the situation".
"There was the possibility that unarmed Japanese diplomats could be an easy target of a terrorist attack," the agency's web site says. "Regrettably, we cannot help saying the government lacked a sense of crisis."
The Okinawa Times frets that the days when Japan was held in high esteem in the Middle East are in the past, and points to the dangers of sending Japanese forces.
"The pro-Japanese feelings in the Arab world used to be a major 'asset' of Japanese diplomacy."
But with Japan at the forefront of support for the US in its war against the regime of Saddam Hussein, "the Iraqis are dismayed, and they have gradually stopped trusting Japan. Now, this sentiment is beginning to transform into hatred."
Doubts over troop dispatch
"The killing of the Japanese diplomats came at a time the debate on SDF dispatch was in the final stage."
"Further squandering of Japan's diplomatic asset and very real threats to the life of SDF troopers - are we really prepared to send the SDF to Iraq at such cost?"
Tokyo's Asahi Shimbun thinks the deaths make their dispatch less likely.
"The fatal attack Saturday has dealt a serious blow to any plan of sending the SDF to Iraq," it states.
"The deployment of ground troops - considered crucial in showing a visible Japanese presence in reconstruction work - now requires further discussion."
In contrast, Nihon Keizai Shimbun believes Japanese troops should still go, despite pressure on the government not to send them.
"These casualties - the first involving Japanese citizens in Iraq - will likely fuel public concern about the SDF's deployment, putting Koizumi's crisis management and leadership skills to the ultimate test," the Tokyo paper says.
"At a time when the attention of parliament and public opinion are focused on the SDF, the deaths of the two diplomats were both untimely and unexpected."
"But the Foreign Affairs Ministry, which is spearheading efforts for the SDF's deployment amid an emphasis on strong bilateral ties with the US, cannot lessen its resolve just because its personnel became casualties."
BBC Monitoring, based in Caversham in southern England, selects and translates information from radio, television, press, news agencies and the Internet from 150 countries in more than 70 languages.