Have you checked out the tactic on this thread yet?
Shameless, Moongsinger, shameless!!

(Nevertheless, a powerful technique and good article

)
Getting back to the original topic, can you make use of tactics to pull off an impressive *offensive* win? The answer remains yes, but it's harder, or more situational. Campaigns, as opposed to full-fledged sustained wars, are ALL about LOCAL advantage. If the AI has a stack of doom able to kill you ten times over, but they're 20 turns away, you can still clean their clock. Strategy and tactics can help create, or take advantage of such a situation. Diversion uses a tiny force to 'pull away' a very large opponent force and to remove power from the local arena that is the real target. Things like bombarding out several squares of a road through the mountains, fortifying there with a few of your best defensive units, can help reduce the AI's local power.
Once you've achieved decisive results on the skirmish level, end the conflict, take your tribute, and keep an eye out for the next opportunity. Use these "Limited" wars for things like: grabbing their only iron/rubber/oil source, taking a chokepoint city, capturing a city with a key wonder, or taking an island.
In that same game with the mountain-based defensive war I discussed above, later I had a series of very short wars to kick *much* stronger AI out of my home turf. By that I mean an offense composed of one archer, one sword, two spears, and six catapults, versus a nation with a few dozen Riders, many swords, pikes, two spears and one archer.
The thing was, their home area was about a 15 turn ride away from my core, and while those piddly units represented my entire field army, all he had *locally* was the two spears and one archer. Not only did I kick them out of my core but I got half a tech as he paid me for peace (50% discount).
If you want an example more like pearl harbor and less like AI-cheese... you might try something like a marine invasion of a so-so defended city in the desert that sat on a nation's ONLY oil supply. The marines took the city (with carrier-based bombardment, vs infantry) and then I landed an infantry ARMY in the city for defense, plus a few others. They then sent about two dozen cav and another dozen rifles and longbows at the city, but could not take it. Their back was broken, they would never regain oil or make a tank, and it took very few units on my part. Lack of oil also meant that their naval position of dominace dried up and disappeared.
Charis