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From about the mid-1980s through the 1990s the 9mmP was the most popular police cartridge, and is still commonly used by the police.  While it uses a .35 caliber bullet, they are usually a bit lighter than the .38 Special--yet velocity is much higher.  This makes the 9mm a more powerful cartridge than the .38 Special overall.  In fact, although the 9mmP also comes in a +P version, the standard pressure version is more powerful than the .38 Special +P.  Additionally the 9mm has light recoil, even in smallish guns.  In service size pistols it holds up to 17 or 18 rounds, and in very small pistols can hold as many as eleven rounds.  While short-barreled 9mms will have less velocity than a longer barreled 9mm, the 9mm is a supersonic cartridge so it suffers less than a .38 Special when shortening the barrel. 

Are there any drawbacks to the 9mm?  It is somewhat ammo dependent so if you don't choose ammo wisely it is going to be less effective than you might wish.   In general however, the 9mmP is a good choice for the private citizen.