Which of those deceptively similar, but disparately perceived, definitions am I being accused of?

The former definition puts "aggressiveness" in a rather positive light, something to which to aspire, and of which to be proud .... so they're presumably seeing something along the lines of the latter definition. I don't think they'd be fearing any sort of physical attack, so it's probably more the "belligerent" angle.
(Incidentally, the 2 definitions you provided are not necessarily mutually exclusive.)

post was made 'against' a perceived outsider, and 'in defence of' an site treasure

Yep, you can get away with more under those circumstances :-)

Cheers,
Rob

In reply to Re: What is "aggressive" argument? by syphilis
in thread What is "aggressive" argument? by BrowserUk

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