The conversation I like to have with the those who believe that 10 round magazines are "enough" for self protection goes like this:
Statistics show that, on average, a trained NY City police officer misses three out of four shots during a fire fight, and it takes two hits on average to stop a threat. Assuming you are as good as a trained police officer while shooting in your home, in the dark, frightened for your life, against a moving target, you will need eight shots on average to stop a single bad guy. The average home invasion involves three bad guys, and occupied break-ins occur on average every 45 seconds in the USA.
Now, it's three AM and you and your wife are sleeping upstairs when you are awakened by the sound of breaking glass. You hear voices downstairs, so you know there is more than one intruder but not how many. They are approaching the stairs. You leap out of bed, toss your wife the phone to call 911, and rush to your closet where you keep two guns: a pistol with 10 rounds, and an AR-15 with 30 rounds. Which do you grab ....
So, if you can choose the appropriate firearm to protect your home, why can't I?