Teapot dome, Japanese internment camps, the deliberate nuclear bombing of civilian centers in Japan and the fire-bombing of Dresden, the corporatist colonization of Latin America, the Red Scare, blacklists, and House Un-American Activities committee, the attempted invasion of Cuba, the massed invasion of Vietnam under false pretenses, the covert bombings of Cambodia and Laos, the overthrow of Salvador Allende in Chile that ushered in the rule of Pinochet...
Then, a historical blip: the 4-year single-term presidency of Jimmy Carter, widely derided as one of the least effective administrations in the 20th century...
... and, bang: covert deals with Iran for hostages, the support of the contras in Nicaragua, the support of right-wing death squads in San Salvador, the bombings in Beirut, and on & on & 9/11 & on until today and the Obama administration.
It's possible that things are worse today than they were in 1978, but it's also likely that 1978 isn't a particularly useful date to compare 2013 to.
Anyway, if you don't find the USA's involvement in Dresden horrifying enough, we can always bring up, say, the Tokyo firebombing – a 100% all-American operation that killed 100,000 on March 10, 1945 alone.
World War II was horrible on a scale that defies description today. There is plenty of horror to go around, from every theatre of war.
War is horrible. There is plenty of horror to go around, from every war. But I do not think that an abundance of horror means that we should do away with the desire for accuracy.
The word "half" is, in this context, purposefully imprecise. To cite it as "42%, based on the fraction of bombers deployed, as reported on an unlocked Wikipedia page five minutes ago" is to deploy needless detail to distract the reader from the main point. ("Do we have reason to believe that the USAAF signed off on, and materially contributed to, the bombing of Dresden? Why, yes.")
It's easy to get lost in irrelevant detail, or to deploy irrelevant detail to make other people get lost. It's one of the reasons they ask young physicists to practice those brainteaser problems ("approximately how many cheese salespeople are there in Utica, New York?"): They need to learn not to fret so much about the shape of the leaves that they're afraid to sketch the forest.
You wanted it to be imprecise because it made your argument sound better. Lets be honest you really did your best to come up with such a verbose example:
"42%, based on the fraction of bombers deployed, as reported on an unlocked Wikipedia page five minutes ago"
versus
"Wikipedia reports that a little less than half the force that bombed Dresden" or
"Wikipedia reports that almost half the force that bombed Dresden"
The latter example required the addition of six letters or one word.
The problematic assumption is that his 'partisan interest' would be to favor (D) over (R). That's not the only possibility. I think that Carter's interests are more in steering (D) and other issues like Israel and Palestine. And perhaps, a little, in glorifying himself - the possibility should not be excluded.
https://en.wikipedia.org/wiki/CIA_activities_in_Afghanistan#Covert_action