President Barack Obama says there was no way to secure a nuclear deal with Iran without first inflicting severe sanctions that made life harder for people in Iran.
Obama is trying to build support for the deal ahead of an effort in Congress to derail it.
South Dakota Republican Senator John Thune says he has his doubts about the deal and says he will likely oppose it unless something changes to make him feel otherwise.
Sen. Thune says, "There are just too many unanswered questions, namely, I think the biggest question is does this deal made us more safe or less safe? Has Iran earned the right to be trusted. Can we trust Iranian leaders who chant death to America? And what are the consequences if this deal fails to prevent Iran to acquiring a nuclear weapon?
Thune says if you answer those questions, it doesn't look like a good deal for America or its allies.