The thought just occurred to me that the blitzkreig strategy I use so effectively probably would not be half as powerful as it is if I razed cities. The real key to my blitzkreigs is that when I take a city, the new borders of my new city usually eat into the borders of the AI's next city down the line. With railroads, using cavalry, panzers, or modern armor, I can often follow chains two or three or even more cities deep in a single turn that way. (I've even been known to build the tracks as I go.) With enough units, I can often take out the continental holdings of a decent-sized nation in three or fewer turns. (I've mentioned before taking all eleven of China's mainland cities in a single turn that way in my current game, although I usually don't get quite that lucky with enemy city placement.)
If I razed cities instead of keeping them, I wouldn't get the instant benefit of eating into enemy borders, so my fast movers would be far more likely to run into blockades of enemy culture too wide for them to cross in a single turn. That, in turn, would give the AI more time to see me coming and draft extra defenders to blunt my attack. That can make the difference between a short, highly successful war that citizens of a Democracy take in stride and a longer, more drawn-out conflict that would pose significant happiness problems. (Not to mention the benefits of getting to any luxury resources in the enemy's territory as quickly as possible, and of depriving the enemy of strategic resources quickly.)
Nathan
If I razed cities instead of keeping them, I wouldn't get the instant benefit of eating into enemy borders, so my fast movers would be far more likely to run into blockades of enemy culture too wide for them to cross in a single turn. That, in turn, would give the AI more time to see me coming and draft extra defenders to blunt my attack. That can make the difference between a short, highly successful war that citizens of a Democracy take in stride and a longer, more drawn-out conflict that would pose significant happiness problems. (Not to mention the benefits of getting to any luxury resources in the enemy's territory as quickly as possible, and of depriving the enemy of strategic resources quickly.)
Nathan
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