Dude was from Sa'udi, good work history, no ties to known terrorists.
West could stop printing visas, but that would mean higher wages and lower house prices.
We'll probably bomb Iran, instead.
Discussion
I don't think the printing of visas is the problem. How many Mexican terrorists does the US have? Almost all American terrorists are white dudes. I think knee jerk reacting to the fact that someone is an immigrant as the cause for their malice is just petty collectivism, which I won't be so hasty to adopt.
You and I will not, but Western governments will. And they will redirect it outwards and away from their profitable rackets
The US currently considers MENA to be White so this would be included in White terrorism statistics if it happened in the US. Germany doesn't collect racial data for... Historical reasons.