The nuclear deal is good for the defense business.
Boeing and other companies wanted to do business with Iran and have sanctions lifted.
Now that Iran is building up the Gulf Arabs want weapons to defend themselves and Boeing and other companies are ready to give it to the Saudis, Qataris, UAE etc.....
Israel and the US are jointly developing anti ballistic missile technology and I read of the notion that Israel’s existing short range anti missile system will be sold to the Gulf Arabs through a US company.
Iran intends to set off nukes. In other countries.