Where I feel the JW's are unique is that they will not go to war against each other or indeed anyone else. You'll get a catholic killing a catholic and there are some horrendous things done in Ethnic Cleansing' where one religion tries to stamp out another but you never get one JW try to kill another.
I'm sorry, but I have a real problem with the thought that some imagine that that is some special sort of "love". How do you figure? You've just stated that ethnic cleansing goes on, right? And how is ethnic cleansing stopped? With war, that's how. Is it loving to sit by and let ethnic cleansing happen? It isn't just catholics you know. Hell, it's very seldom Catholics. Would it be loving to sit by and let your family, your fellow man, be run from their land, perhaps raped, killed, etc... simply because you have a group of mean-spirited old Auto/theocrats in Brooklyn you are committed to answering to?
Never imagine it so.
JW's don't refuse military service because they are more loving people than Catholics, they refuse military service because they believe that there is a biblical prohibition against it (as told to them by the GB). There is no such thing, but even if you can make a tenuous case that there is, you certainly can't make the case that it is based on "love".
Why, pray tell, do you reduce it to "a catholic killing a catholic"? I mean, sure, that has happened, but that is not generally the gist of war. Sure, a JW may never kill another JW in a war, but guess what, a JW won't ever save a JW from the atrocities of a war either.
JW's didn't kill anyone in WWII, but they sure are better off (read: in existance) because some people did.
To address your comment on ethnic/religious cleansing, JW's could have a policy or doctrine of abstaining from any sort of ethnic or religious "cleansing" type wars. They don't, in fact they believe, and this is in writing, that God did favor one ethnicity over all others, and they further believe that God favors one religion over all others. They instead have a doctrine that doesn't allow them to go to war at all, no matter how just the war. That policy is based not on love, but rather on the concept of "being no part of the world".
Exactly where a christian should draw the lines in his or her attempt to "be no part of the world", is fodder for another discussion altogether, but it's worth asking if JW policy in that regards makes a damn bit of sense? Are taxes Ceasars only due? Doesn't "Ceasar" run/exist by virtue of community participation in most cases? One more area where the governing body should have just shut the hell up, and let individual conciences work like..... well... individual conciences.
It's certainly not as if JW's are revolted by the concept of killing to solve problems. That is the very core of their interpretation of the scriptures on Armageddon (I stress "their interpretation", because it isn't as if the Bible is clear and plain on just what "armageddon" really even is. It's simply the leaders and the followers of JW doctrine's choice to believe it means wiping out most of mankind; in reality the one mention of "har-maggedon" in the bible, is tucked into a group of highly symbolic verses.).