Visiting the WTC "Ground Zero"

I don't really get the uproar concerning Ahmadinejad's request to visit "ground zero" in NYC. It seems to me we would want the leader of every muslim country to visit the site of the most horrendous terrorist attack in recent history. Not letting him visit simply provides another insult to Iran that will help keep him in power. Besides, Iran didn't attack us on 9/11 (just like Iraq didn't). However, Saudi Arabian nationals did attack us. Yet, Saudi Arabian Prince Alwaleed bin Talal bin Abdul Aziz Alsaud was allowed to attend a memorial service at Ground Zero with Mayor Rudy Giuliani in Oct. of 2001.