The first real Islamist terrorist attack in the United States occurred with the first bombing of the World Trade Center in 1993. Prior to that Islamic terrorism had not really occurred in the United States out side of the occasional focused attack on a Jewish or a pro democracy Iranian groups. Bill Clinton was president until 2001.
http://www.johnstonsarchive.net/terrorism/wrjp255a.html
After 2001 Islamic terrorism increased dramatically in the United States. George Bush and Barrack Obama were Presidents in the 16 years after that horrific event on 9/11. Initially George Bush promised to tighten border security, and deport those who had overstayed visas, etc. However, the Barack Obama administration gave the impression that the US was open to anyone who could get here legal or otherwise.
In the partial year since Donald Trump became President in 2017, he has attempted to stem the tide of Islamic immigration, however his efforts have been thwarted by Federal Judges and suits brought by State Attorney Generals. Those suits are currently making their way through the courts.
I think terrorists who attack in the US should be identified by the President they entered the US under. The latest terrorist attack was carried out by an Obama immigrant.