Re: In a quandary
Well then, what is it that you would like to accomplish? What is it that you are likely to encounter? Here in California we don't see many knife attacks. They happen, but they are actually pretty rare. Spending a great deal of time training specifically for knife attacks probably isn't too valuable unless you are a prison guard. Most assaults, at least street assaults, are with strikes and kicks here and that's an area that aikido serves pretty well. So does any number of other arts as well. One really important consideration is at least some legal training to make sure you don't go too far and turn into the aggressor and end up in jail.
Aikido may not be the best course of action for you, since we don't know anything about your environment or lifestyle. Give us a little more information and perhaps someone here can give you better advice.