The following op-ed was written by and submitted exclusively to Breitbart News by Sen. Marco Rubio (R-FL).

After years of negotiations and repeated concessions, the Obama administration has now concluded an agreement that leaves Iran, the world’s foremost state sponsor of terrorism, as a nuclear threshold state.

The accord concedes a vast enrichment capacity; punts on the question of previous military experimentation with nuclear technologies; accepts both a heavy water plant as well as a hardened underground enrichment facility; and envisions a ramped up Iranian research and development program.

In several years, Iran could be free of a multilateral arms embargo just as its terrorist agents are flush with cash and expanding their illicit efforts around the globe.

The agreement has a limited duration and once it expires (if Iran has not already cheated) Tehran can dash to the bomb. If I am elected President I will abrogate this dangerous agreement and force Iran to permanently end its nuclear ambitions.

For decades, Republican and Democratic presidents have consistently attempted to deter our adversaries and persuade our allies not to pursue sensitive nuclear technologies. The Obama administration’s flawed deal with Iran contravenes almost seven decades of U.S. nonproliferation policy and takes the world in the opposite direction from President Obama’s 2009 aspiration in Prague of “a world without nuclear weapons” toward a highly proliferated Middle East and a more dangerous world.

As President, I would strive for the closure of Iran’s nuclear program as opposed to the mere conditioning of its nuclear activities. Iran would be forced to stop subverting its neighbors and threatening Israel. Human rights would assume a higher place in any negotiations—as part of any agreement Iran would have to honor international norms on treatment of its citizens.

When I enter the Oval Office, I will act quickly to undo this agreement. I will reinstate the principle that has long guided American policy, namely that Iran cannot have mastery of dangerous nuclear technologies. I will reimpose the sanctions waived by President Obama and work with Congress to impose new crushing sanctions on Iran’s leaders for their brutal human rights abuses and ongoing support for terrorism.

I will invite our European allies to join us in this effort, but at the end of the day American security is not determined in Brussels or Vienna. Americans expect our leaders to do what is right for their safety and that of their children and grandchildren regardless of what the international backlash may be.

I will give Iran a choice: change your behavior, or face the collapse of your economy due to U.S. pressure. Despite its inflammatory rhetoric, Iran’s clerical dictatorship has immense vulnerabilities. Iran’s economy continues to suffer from inflation and unemployment while rampant corruption plagues the state at all levels.

A strategy of pressure will not just focus on Iran’s economy but also its regional position. For Iran’s leaders to make painful concessions they have avoided thus far, they need to feel that the walls are closing around them. The U.S. should undertake a systematic effort to isolate Iran in the Middle East. The Islamic Republic, its clients and proxies, should find no sanctuary in the region. The U.S. must do all it can to counter Iran’s nefarious plots in places like Iraq, Lebanon, Gaza, Syria or Yemen.

Perhaps most importantly, we need to stop neglecting the fact that the principal victims of this despicable regime are the Iranian people. It is they who have to bear the burden of the mullahs’ repression and misrule. In our quest for an arms control agreement, we have given the regime a pass on how it treats its citizens. As President, I will continue to speak loudly on behalf of the Iranian people and support their desire to be free.

Iran’s people are the most pro-American public in the Middle East, and they should know that the United States will always stand up for their rights. One of the great tragedies of the Obama/Clinton record on Iran has been the silence. Silence during and since the Green Revolution that nearly overcame clerical despotism in June 2009. Silence for fear of offending the very officials that oversee abuse and terror that Obama administration officials now proudly praise as “patriots.”

It is clear that Secretary Clinton is no more ready for this challenge than President Obama was. She and her team started the secret diplomacy with Iran that led to this deeply flawed agreement. Within hours of the deal’s announcement she hailed it as “an important step.”

In the end, this should have been a confrontation between a superpower and an illegitimate third-rate autocracy. Instead, the Obama/Clinton team settled for trading carrots and sticks and hoping for elusive signs of moderation from cruel theocrats. President Obama’s capitulation has made it more difficult, but not impossible, to prevent a nuclear Iran.

Only a determined strategy of coercion by the next President can still ensure that the Islamic Republic abandons its quest for nuclear weapons and rolls back Iranian hegemonic ambitions in the Middle East. The immediate challenge for Congress is limiting the damage until January 2017.

Marco Rubio represents Florida in the United States Senate and is a candidate for the 2016 Republican nomination for President. Follow him on Twitter @marcorubio.