By Mike Dougherty

By Mike Dougherty

PHILADELPHIA (CBS) — Secretary of State John Kerry was in Philadelphia Wednesday to talk about the Iran Nuclear Deal. This comes as two local US Senators are throwing their support behind the plan, albeit cautiously. Senators Bob Casey and Chris Coons both expressed reluctance to get on board.

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Kerry says this is the best option, the only option.

Without the deal, Kerry says Iran would be free to continue developing their nuclear program, which was on the verge of a breakthrough 19 months ago. Today, they are complying with the international agreement, allowing constant monitoring of their program. Kerry says that monitoring will continue forever because they can’t be trusted. If Iran were to cheat…

“They would have to come up with a complete and completely secret nuclear supply chain. A secret source of uranium. A secret milling facility. A secret conversion facility,” Kerry explained.

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Kerry understands the reservations many leaders have about the plan, particularly the concerns of Israeli prime minister Benjamin Netanyahu.

“Our support for Israel also remains rock solid,” Kerry said.

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Kerry hopes lawmakers approve the plan because he believes it’s the best way, at the moment, to keep the Iranians from developing a nuclear weapon.