Perhaps it is because quite to the contrary, the public doesn't think we're at war at all. We're just killing off terrorists who aim to harm us, with surgical, precision strikes.
And yes there is malice. If you seek to hide civilian casualties your excuse cannot be the disinterest of the deceived. The lies which hide drone terror by framing it as a war, these lies cause great human suffering by prolonging the inexcusable. How could the assumption of "all adult males killed must have been guilty" not be evidence of deception?
Even if we were so innocent of the situation to assume politicians are lying to protect us, they would still be lying. I don't know your ethics but mine do not encompass knowingly spreading lies. Especially when it's done to protect one's position. A position of great power, I must add.
Journalists have the means to uncover these lies. When they choose to spread them instead, because this is the easier option, they become complicit. It may not be malice in the sense of "evil for the sake of it" but I wouldn't set the bar down there.
You are talking about something which is usually kept secret within the "state secrets" cabinet. Your expectations seem misconfigured for this topic. There's no way the CIA/DOJ/FBI would willingly allow that level of information to make it into wide circulation and the current administration has gone to unprecedented lengths to prevent further leaks.
I tend to agree with you that the media news coverage in the US tends to focus mostly on certain specific military attacks (where the US government claims we either hit or believe we hit a "top leader" in whatever group) or where the US military strike was on bad/stale information (eg. we killed western hostages or a Doctors without Borders hospital in Afghanistan). I am not conflating drone strikes with other military strikes -- I am combining them because I see them as part of the same issue.
I tend to see the media as willingly reporting only what little information is available from the only source, the White House via the US military. Journalists are reporting one very biased side of the story without making any significant effort to find other sources (because there usually are none). From a journalistic ethics standpoint, this _is_ malicious.
I view US drone strikes "on terrorists" within a context of (what I believe to be) known information about our CIA drone strikes (which, granted might be outdated or otherwise inaccurate and is basically unverifiable):
* "signature strikes" are designed to attack targets based on data points without knowing their identity
* a "double tap" strike is when first responders are attacked immediately after a previous attack on the assumption that they know who was killed and care about the terrorist target and not the innocent victims of the first strike
* weddings, funerals, and other public gatherings are attacked on the probability that terrorist or terrorist sympathizers will attend
* an "enemy combatant" is any male of combat age (15-50, IIRC) [1] -- this is especially troublesome for US propaganda. See [1] for "deliberate intent to deceive the public in the media coverage of civilian victims of Western attacks". It might not even be "conclusive evidence", but I still think that standard is too high for any topic which is covered by national security where we will always be in an information "fog of war".
[1] http://www.salon.com/2012/05/29/militants_media_propaganda/ [2]http://www.imdb.com/title/tt3297330/
More probable explanation is that viewing public's sympathy suffers from inherent biases and the media simply follows those biases. It's a well-known fact that media prefers headlines that are more likely to trigger emotional response.
Also non-Western civilian victims have been a lot more frequent and the media has a bias towards reporting events that stand out such as unintentional killing of Western hostages by a drone strike.
(Not claiming this outcome is moral - just saying that it may unfortunately arise without malicious intent on the part of the media)