Being a member of the IRA is not quite the same as being Irish. The Irish celebrate St. Patrick's day, as do the IRA most probably, being Irish. Not all Irish are members of the IRA however, so your point is utter gibberish.
And whoever said you are, I quote 'good english folk'? Are you the self appointed judge of what is and isn't 'good' and 'english'?! You make yourself sound like a hobbit living in some rural, idyllic paradise resembling the shire. I expect you live in Hounslow though, not quite the same eh.
What exactly are you being denied? The right to wave your national flag? No. The right to wave a flag with a worryingly extreme right undertone? Good.
If you feel so strongly about it, and the fact that the scots get away with wearing their tartans and blowing their bagpipes, I suggest you come to the next home game covered in bells and waving handkerchiefs, and morris dance the players out of the tunnel as the game begins.