Bring a large pot of salted water to a boil. Add the pasta and cook until tender, about 10 minutes. When the pasta is done, drain it, cool under cold water, drain again and pat dry.
Meanwhile, grill or broil the tuna 2 to 3 minutes a side only or until charred on the outside, but rare on the inside. (If you don't like tuna rare, substitute canned tuna which you don't cook.) When the tuna is done remove it to a plate for later.
In a large mixing bowl combine the olive oil, corn, peppers, red pepper flakes and optional mayonnaise. Toss the pasta with the olive oil, corn and peppers.
Portion out the pasta. Cut the tuna into thin diagonal strips and pile them in the center of the pasta; garnish with chives.