In other words, Reaganomics contributed to Islamic terrorism.

Or, to make it clickbaity-ish, "caused".

We should also be critical of the term 'terrorism': it is often a buzzword used to shut down criticism of protest groups. In this case it does hold up, though.

Did Reagan administration sanction Iraq while providing them with weapons for their war against Iran?
IfaIk, the sanctions were established later, after the invasion of Kuwait in 1990, under George H. W. Bush.