You're giving validation to their actions through your own logic. Therefore, I'm calling you out on being an idiot. I can see the sort of parallels between calling someone a terrorist, and slandering someone over the mass genocide of their entire culture into the millions.
I'm giving validation to the idea of "if you insult, prepare to be insulted back." Calling Arab people terrorists is one of the most reprehensible insults that one can give them. It labels them as violent, bllodthirsty, moronic extremists and the insult puts them amongst the lowest scum that inhabits the earth. What's worse is that it validates the murder of these activists - something you obviously have no problems with. Telling an israeli to go back to auschwitz simply tells them to die. It doesn't justify that death, it doesn't insult them. It just tells them to die.
But all that is fluff because it all comes down to the following: If israel is going to throw these awful accusations around, then it is more than fair for others to throw insults back. That is all. Don't get ahead of yourself.
SUGGESTIONS FOR REBUTTAL:
*israel deserves to exist because of the holocaust
*Existence of israel ensures that no new holocaust occurs because the jews are under constant threat
*Opposition to israel is tantamount to new anti-semitism
*The hyphenation of anti-semitism is evil
*jews are God's chosen people and therefore the jews who choose to live in israel can do as they please