This advertisement ran in an issue of the Wisconsin State Journal Monday.
Tumbledown general manager Marc Watts told The Milwaukee Journal Sentinel that the ad was to remind young people about the importance of 9/11's anniversary.
After being overrun with angry comments on their Facebook, Tumbledown issued an apology for the promotion.
They doubted that they were be open on Wednesday, as of Monday night.
Commenters from all over the country said how hurt they were over the course's promotion.
Tumbledown's management didn't mean to offend anyone.
Now the golf course is unclear whether they'll be able to open at all on Wednesday for fear of violence.
Ryan Broderick is a reporter for BuzzFeed News and is based in London.
Contact Ryan Broderick at email@example.com.
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