He was fine with other dogs as a puppy until a local arsehole let his much larger beast go violently batshit at him in passing. Poor Foof was indelibly terrorised, becoming regrettably super-anxious and aggressive around a certain type of larger, dominant dog ever since. It's such a shame because he lives to play and there aren't any smaller, 'safe' dogs who can keep up with his insane athleticism; they get sick of puffing along in his wake and lose interest.
And here beginneth my rant about this kind of dog-related bullshit. Felix may be a mouthy arsehole on occasion but he's too small to be dangerous and is leashed in public 98% of the time- 100% around other dogs. We try really hard to keep a foot on him because we, you know, recognise that his behaviour can be problematic.
Conversely, there is an expanding cohort who don't understand the fundamentals of humane interaction and have unfortunately taken up dog-wearing; canine acquisition as it pertains specifically to personal optics.
Bucolic dogwankers are an ancient evil but only really troublesome when they retire and insist on coming into town. This newer urban strain is far more ubiquitous. They drive black SUVs. Or electric cars. Wear stupid hats, brand-new $1200 walking boots and spend too much time at the barber (for everyone who used to cop Sobranies and get their shit buzzed at the tobacconist, it's back to being barber now, mmokay?).
They are generally fairly auto-enraptured and empirically deficient. The females have taupe lowlights, totally sustainable Scandinavian goose down and osteopenia.
Most of them don't know or care that their oblivious, self-regarding fuckery can inflict hassle and even danger on unsuspecting strangers, but here's a clue for the curious: if strangers are having to fend off your bossy-arse, uncontrolled accessories because you won't even call them back to you (the guy at the leadership retreat said raising your voice was beta-signalling), you're being a selfish, stunted cunt. You're as shit at walking your dog as you are at managing everything else (see: tech industry). Everybody hates you. Leash the fucking things.