Beginning in 2010, I helped champion in Congress an aggressive and punitive series of sanctions against Iran because we faced an Iranian nuclear program that was spinning unchecked and out of control. The Iranian regime with a nuclear weapon posed — then and now — an existential threat to the State of Israel, and dangerously threatens our own national security interests.

Bottom line: Iran possessing a nuclear weapon would be a game-changing event that cannot and will not be allowed. That was true then — and it remains true today.

The question before us now is whether this deal is the best way to reach our goal, or whether the best way forward is continued Congressional sanctions, even as other nations around the world begin to lift their own. To date, the sanctions the U.S. led the global community to impose worked: they crippled Iran’s economy and compelled its leaders to face us at the negotiating table.

By including China, Russia, and our European partners, this crushing economic pressure, combined with diplomacy, has produced an unprecedented combination of ways to prevent Iran from obtaining a nuclear weapon. Just as important, inspectors will have unprecedented access to Iran’s facilities, so that we can better understand Iran’s capabilities, stop a program currently designed to produce a nuclear weapon, and be better prepared to detect any covert activity. This deal does not take any military options off the table for the next president if Iran fails to live up to its end of the agreement. In fact, we will have better intelligence as a result of this deal should military action become unavoidable. But rejecting it and leaving only U.S. sanctions in place without the essential support of the international community will move us closer to military confrontation. Sanctions worked when the world community came together, choking off the Iranian economy. In a meeting earlier this week when I questioned the ambassadors of our P5+1 allies, it also became clear that if we reject this deal, going back to the negotiation table is not an option.

I have decided to support this deal after closely reading the agreement, participating in multiple classified briefings, questioning Energy Secretary Moniz and other officials, consulting independent arms control experts, and talking with many constituents who both support and oppose this deal. Here is why I believe this imperfect deal is worthy of Congressional approval:

First , Iran made essential concessions in the deal. After the failure of the 2004 Paris Agreement, Iran was defiant; it refused to negotiate seriously, it was uncooperative with international weapons inspectors, and it vowed never to cave to pressure and dismantle its nuclear production, which increased dramatically during the Bush years. Now, Iran has signed on to a sufficiently verifiable and enforceable deal that cuts off all paths to a bomb and has its entire nuclear supply chain closely monitored for years to come. A deal like this, widely supported by independent nuclear arms control experts, was unimaginable just a few years ago.

, Iran made essential concessions in the deal. After the failure of the 2004 Paris Agreement, Iran was defiant; it refused to negotiate seriously, it was uncooperative with international weapons inspectors, and it vowed never to cave to pressure and dismantle its nuclear production, which increased dramatically during the Bush years. Now, Iran has signed on to a sufficiently verifiable and enforceable deal that cuts off all paths to a bomb and has its entire nuclear supply chain closely monitored for years to come. A deal like this, widely supported by independent nuclear arms control experts, was unimaginable just a few years ago. Second , this deal will provide international nuclear inspectors with access that they otherwise would not have had — and never will have if we reject this agreement. We will begin robust worldwide monitoring of Iran’s nuclear supply chain — uranium production, plants that convert uranium into a centrifuge-ready gas, centrifuges, uranium stockpiles, and spent nuclear fuel that contains plutonium — and inspectors will retain the right to request access to suspicious sites forever.

, this deal will provide international nuclear inspectors with access that they otherwise would not have had — and never will have if we reject this agreement. We will begin robust worldwide monitoring of Iran’s nuclear supply chain — uranium production, plants that convert uranium into a centrifuge-ready gas, centrifuges, uranium stockpiles, and spent nuclear fuel that contains plutonium — and inspectors will retain the right to request access to suspicious sites forever. Third, while I’m skeptical that Iran won’t try to deceive us and our partners in this agreement, we’ll be in a better position to catch those attempts due to the monitoring and verification mechanisms that this deal secures. If Iran pursues a nuclear weapon, international inspectors and intelligence operations will know faster than ever before. We will then be able to snap back all of the American and United Nations sanctions, even unilaterally, and all options — including military action — will be on the table.

Iran will still be disruptive in the Middle East and fund terrorist activities. This regime will continue to deny Israel’s right to exist, the Quds Force will still be listed as a terrorist organization, and Iran will continue to exacerbate tensions with our allies in the region. But Iran would be exponentially more dangerous to Israel and the entire region with a nuclear weapon.

Israel’s security and America’s national security interests are fundamentally aligned. Congress must continue its unwavering commitment to ensuring that Israel retains a qualitative military edge in the region — an effort I will continue to steadfastly support. I have not only consistently voted for Israel’s full foreign assistance package, but have also added funds for innovative and effective defense projects, such as Iron Dome. I will fight in Congress for a new Israel defense aid package, because we must continue to fund the new technologies of tomorrow that will keep families safe from conventional missile and terrorist attacks.

There are legitimate and serious concerns about this deal. For example, I would have liked to see a period shorter than 24 days to resolve disputes over access for inspectors. The U.N. embargoes on the sales of arms and ballistic weapons to Iran should have remained in place permanently, instead of lapsing after five and eight years. Hostages remain in Iranian custody. We will have to work hard to fight Iran’s malign efforts to wreak havoc in the region. While all of these issues are important, no issue matters more than ensuring that the Iranian regime does not have a nuclear weapon at its disposal.

If we reject this deal, we do not have a viable alternative for preventing Iran from obtaining nuclear weapons. Without a deal, and without inspectors on the ground, we will be left in the dark as Iran resumes its pursuit of a nuclear weapon, with only months to go before it could enrich enough fissile material for a bomb. Without a deal, our options will be limited to insufficient unilateral sanctions, an invasion with yet another massive and costly land war in the Middle East, or a bombing campaign that offers nothing more than short-term gain under the best-case scenario.

Our goal has been, and remains, to prevent Iran from developing a nuclear weapon. We have far more ability to achieve that outcome if we approve this deal‎.