Sad to say and although i admire the heroism above, in this day and age unless its my family/friends, it just not worth the possible outcome You can be as tough as a coffin nail, but no one is stopping a bullet and unless your professionally trained, getting a knife of someone is no easy task and you will get cut in the process even if you succeed in the long run
A buddy of mine got knifed in Jamaica when he was 18, he didnt even know during the ruck, it wasnt till he got 50 yards down the street that he realised his intestines were hanging out, on another day, he wouldnt have lived to tell the story.