I mean the Iranian regime would under no circumstances allow an Iran-Israel game.
Also if any Iranian athlete would actually compete against an Israeli citizen, the athlete could immediately apply for asylum.
So Iran would boycott the game against Israel.
The German football team would face pressure to boycott the Iranian team to show solidarity against antisemitism.
If the Germany-Iran match would still take place, I would expect a large number of German fans carrying Israeli flags to the stadium (similar to the rainbow flags recently in protest against Hungarian discriminatory law).
If the stadium is full of Israeli flags, the Iranian team would immediately cancel the game.
If Fifa forbids German fans of carrying the Israeli flag or the star of David in any form to the Germany-Iran match, Fifa would face a massive backlash in Germany and the US. Then people would accuse Fifa of supporting antisemitic policies of the Iranian regime.
Agree with this 100%
I think maybe the American posters here who are not really into soccer don't truly appreciate the extent of the ramifications of such a shitshow World Cup lol. Nothing comparable would happen in American football or basketball as these sports simply don't generate the same level of worldwide interest.
What you mentioned of Germany and the nuances of any Iranian boycott, we can safely say nearly every Western nation would have the same reaction and pushback.
I think the Iranians would very likely start making noises in the same week the draw was made (i.e. first week of December 2017) about boycotting the match in June 2018. This would then become the headache of not only Fifa but any other Western nation placed in the same group.
Serbia refusing to play Kosovo would likely generate a similar reaction in Western nations - i.e. decide to boycott the match against Serbia or not. Less so than the Israel situation as peripheral countries like Australia or Norway wouldn't care, but still significant.
I really wonder how FIFA would handle all of this (including the other clashes) happening all at once, in one tournament. Lucky for them the politically problematic countries are also minnows.