Kerry blue? Did you research the breed first?
Kerry blues are one of my absolutely favorate breeds. I breed show dogs. I have a lot of dogs, relatively speaking (a kennel license too...) But I don't have a kerry blue. Why? They are one of the toughest terriers around.
I like my boys to get along. I can run three intact adult males in the same run without a problem. Kerry blues? You can't even keep more than one intact male or you will have major fights. Even the girls are very difficult, strong minded dogs that can and will take on any and every dog.
I don't own a kerry blue...I admire them from afar.
What to do? Remember what you own, it's not going to be easy. Start with a private obedience class and lessons in getting him to pay attention to your face. Once you have this downpat in an environment with no distractions, start a group obedience class and go consider every walk outside a training opportunity. Be positive, but quite firm with corrections.
This will take time and you will never have a dog you can completely trust around other dogs but you WILL have a dog that you can take for a walk peacefully.
A few other notes, use only a 6' leather leash and a well fitting slip chain collar. No flexis, no flat collars. Learn to "Pop" the slip collar and change your direction when walking -- you are in pulling contests now and you won't win. It's like walking a horse -- if they start to pull one way, you change direction and throw them off balance -- you'll never win a pulling contest with at 1,200 lb horse, nor will you with a kerry blue! Technique is everything.
Have fun with him...wish I could have one, but not with my other dogs here.
PS -- 12 champions is nice for sure, but plenty of show dogs have 4 full generations of all champions behind them. I have a litter here like that, but if half of them are show potential themselves, I'll be very pleased. The others will be very special pets.