Two historic events are in progress today, August 14. The first is the arrival of Secretary of State John Kerry in Cuba. The second is President Obama’s continued campaign to secure Congressional approval for his flawed nuclear deal with Iran. These two dangerous developments represent the convergence of nearly every flawed strategic, moral, and economic notion that has driven President Obama’s foreign policy, and as such are emblematic of so many of the crises he has worsened around the world.

To fully understand what we’re dealing with in regards to Iran and Cuba, we have to understand who we’re dealing with. In Iran, we face radical Shia clerics who wish to one day unite the world under their version of Islam and who believe this will only happen after a cataclysmic showdown with the West. These leaders have been directly responsible for the deaths of hundreds of Americans and refuse to stop financing terrorists that seek to kill Americans and wipe Israel off the map.

In Cuba, we face proudly anti-American leaders who continue to work with nations like Russia and China to spy on our people and government; who harbor fugitives from American justice; and who stand in opposition to nearly every value our nation holds dear by violating the basic human rights of their own people, preventing democratic elections, and depriving their nation’s economy of freedom and opportunity.

Centuries of global affairs tell us the best way to affect an outcome with volatile leaders is through strength and example, while the worst is through weakness and concession. Yet weakness and concession are the preferred tools of statecraft for this administration.

President Obama has not only permitted Iran to retain its entire existing nuclear infrastructure, he has also endorsed the construction of a full-scale, industrial-size nuclear program within 15 years. He has conceded a vast enrichment capacity, preserved Iran’s fortified underground facility, and failed to secure “anytime, anywhere” inspections. He has virtually guaranteed Iran becomes a regional power with the ability to build long-range missiles capable of hitting the U.S. homeland. And on top of all this, he wants to hand Iran $100 billion in sanctions relief, which will be used in part to fund Hamas and Hezbollah, promote instability in Bahrain and Yemen, and prop up Bashar al-Assad in Syria.

The negotiations with Cuba have proven equally one-sided. President Obama has rewarded the Castro regime for its repressive tactics and persistent, patient opposition to American interests. He has unilaterally given up on a half-century worth of policy toward the Castro regime that was agreed upon by presidents of both parties. He has ensured the regime will receive international legitimacy and a substantial economic boost to benefit its repression of the Cuban people, which has only increased since the President announced his new policy.

Beginning on day one, I will undertake a three-part plan to roll back President Obama’s deal with Iran. First, I will quickly reimpose sanctions on Iran. I will give the mullahs a choice: either you have an economy or you have a nuclear program, but you cannot have both. I will also ask Congress to pass crushing new measures that target human rights abuses and the sponsorship of terrorism.  Second, I will ensure our forces in the Middle East are positioned to signal readiness and restore a credible military option. Third, after imposing crippling sanctions on Iran, I will link any talks to Iran’s broader conduct, from human rights abuses to support for terrorism and threats against Israel.

I will undertake an equally bold plan to roll back President Obama’s concessions to the Castro regime. First, on day one, I will give the Castros a choice: either continue repressing your people and lose the diplomatic relations provided by President Obama, or carry out meaningful political and human rights reforms and receive increased U.S. trade, investment, and support.  Second, I will restore Cuba to the state sponsor of terror list until it stops supporting designated Foreign Terrorist Organizations, helping North Korea evade international sanctions, or harboring fugitives from American justice. Third, I will do everything in my power to provide support to Cuba’s pro-democracy movement and promote greater access to uncensored information for the Cuban people.

These are the actions required to restore the safety and security President Obama has cost us through his diplomacy with dictators. When it comes to the challenges posed by Iran and Cuba, our task is straightforward – we must prevent Iran from gaining a nuclear weapon and we must guarantee that the United States stands on the Cuban people, not their oppressors. But we also know that 'straightforward' is not a synonym for 'easy.' Our safety and security will require what it has always required: strong, principled leadership. And that is exactly what I intend to offer our nation and the world in the years ahead.

Republican Marco Rubio represents Florida in the U.S. Senate. He is a member of the Senate Committee on Commerce, Science and Transportation and was a candidate for the Republican nomination for president in 2016.