Yeah but you would probably get away with it as long as you didn't announce your arrival and intent to have a march in honour of rangers and walked (running would only spark things off) quickly through the city visiting every place only once. And finishing up in a Garda station.
Thick thing is, orange is in the flag.
Ok, should I only bring green color clothes to Ireland then??
Nah cause then you'll be immediately identified as a foreign tourist gábeen and someone will eventually get thick with you about some countries foreign policy or taking our jobs or something. Well, probably not, but thats a worst case.