Nuclear Development and Middle East Stability

President Obama says Iran's nuclear program has been "halted" -- but a final settlement seems far in the future.  Talks about the program will resume next month, with Iran, Britain, China, France, Germany, Russia and the United States back at the table.  Their deadline for a real deal is the end of June — but there's talk of another extension. Senate Republicans, and some Democrats, want tougher sanctions, claiming that will encourage Iran to make new concessions, but Obama has threatened a veto.  House Speaker Boehner has injected Israel into the mix by inviting Israel's Prime Minister Netanyahu to address Congress -- while he's running for re-election.  Are domestic politics in all three countries threatening diplomacy with nuclear weapons at stake?