Is it possible to sabotage Bitcoin by accumulating coins (through purchase, theft, or exchange breach, etc.) and then deliberately destroy the wallet that contains the key to these coins?
Presumably these coins are henceforth lost, essentially.
The way to do this with greater certainty would be by actually sending the bitcoins to an inaccessible address, rather than deleting the wallet. Never know when some pesky thief, who copied the wallet via a trojan a while back, might decide to access the coins himself.
But really, you'd just be redistributing wealth to all the other holders of bitcoins. It would take acquisition of a significant majority of the bitcoins in existence before any lack of liquidity affects the marketplace. Right now, we're only using 4 digits beyond the decimal point, right? So there's still plenty of room left for finer divisions. Even acquiring (somehow) and wiping out 50% of the 6-7 million bitcoins that have been mined so far probably wouldn't require any greater accuracy.
And then the remaining 14-15 million bitcoins eventually get mined.
Any attacker attempting to use this method just to "sabotage Bitcoin" is not one to be feared, but rather laughed at.
But hey, if you know anyone wanting to burn their own money, have at it:
1BitcoinEaterAddressDontSendf59kuE