On that line of thought, let's consider the following:
Well in TNG they're introduced as a former enemy they fought for years to a bloody stalemate.
...While simultaneously making it clear that their weapons can't hurt Starfleet ships of the
Galaxy generation at all. One might conclude that the threat they present is that of classic "asymmetric warfare" where superior Starfleet firepower would guarantee UFP triumph but political reality prevents it from being applied.
Note that despite there being a "stalemate" in the sense that UFP and Cardassia struggle to stabilize a common border, it seems that all Cardassian conquests outside a pitiful half a dozen lightyears from their homeworld (that is, outside Bajor) were stripped away by Starfleet advances, leaving all space around Cardassia and Bajor "neutral" (albeit with Cardassian sympathies) at the start of DS9. This leads me to speculate that Cardassia was thoroughly beaten until the time came to consider "invasion of Japanese mainland" - and Starfleet decided not do to that, knowing that Cardassians would fight to their deaths. And having thus exposed their softness, the Feds had no option but to conclude the war by negotiating from a seeming point of weakness.
Running into late TNG early DS9, they Federation considers maintaining the peace treaty, which they basically routinely violate in spirit if not in paper, more important than the well being of their own colonists on the border.
In line with the above, this might be another sign of Cardassian weakness: the Federation dare not start another war with them, because that would lead to total annihilation of the Union, and the Federation doesn't want that. Apart from altruistic reasons, the Cardassians might e.g. be too valuable as buffers against the Breen, a shared enemy.
In mid DS9, the Klingons bring them down to their knees with virtually now effort.
But interestingly, while they seem to make good progress in wake of a surprise attack, they are fought to a standstill once the Cardassians get a warning. Surely the Klingons would have pressed on at this point, despite their diplomatic problems with the Federation, and would have made the UFP Council face the fact of them being in control of the Union now - but apparently Cardassian military force alone stopped them from achieving this no doubt desperately pursued outcome.
This might tell us more about the mechanics of space warfare in Trek than about the relative sizes of Klingon and Cardassian starfleets. DS9 explicitly shows us what TNG only hinted at, and TOS indirectly implied: thousands of starships will have a hard time conquering a single planet if said planet has orbital fortifications in place. In other words, defense is cheap and effective, while offense is expensive and often futile.
This would lead to Cardassia being an offensive threat only to primitive cultures, and indeed it is famous for subduing such - but also just powerful enough to pass the defensive power threshold needed for stopping superpowers.
It was only once they joined the Dominion that they really became a power to be reckoned with in some ways, and even then they were only an extension of the Dominion.
Significantly, their weapons also appeared to receive a crucial upgrade at that point. Having proceeded from the wimpy pink beams of TNG to the only slightly more powerful thin, swirly amber ones in early DS9, they now sported the thick, bright golden beams that cut Federation ships with the same ease Starfleet's similar-looking beams cut Cardassian ships.
Sloan was talking about a cold war with the Romulans.
And no doubt lying his eyes and ears full, as usual. But possibly in the narrower context of who controls the now strategically crucial wormhole region - because in that game, Cardassia would definitely have to be counted in even if it were a featherweight.
Well we don't know much about the Federation-Cardassian War. Except that it was from circa 2347-2367.
And interestingly, according to "The Wounded", the Setlik III incident of 2347 seemed to end in a Cardassian
apology - which suggests that it did not represent part of the war as such, but only an early lead-in event that was followed by more years of waiting.
Timo Saloniemi
