On July 14, P5 1 and Iran finally reached a historic deal on the Iran nuclear issue, formally named the Joint Comprehensive Plan of Actions. Very few international issues have attracted so much attention as this one. Though it is primarily a big success for the United States, it also means challenges for Obama's administration.

There is no doubt that the deal in no way signifies the conclusion of the nuclear issue. It is predicted that it will be more difficult to implement the deal than it was to negotiate it. American and Iranian hardliners and Israelis and Saudis will be making every effort to sabotage the implementation of the deal as they did in opposing the negotiation of the deal. But the peaceful resolution of the issue and the reconciliation between the United States and Iran will be an irreversible process since there are more supporters than opponents.

The success of U.S. diplomacy in this regard firstly lies in finding an economical way to prevent Iran from developing nuclear weapons. There are two kinds of points of view regarding the ways to address the Iran nuclear issue: the military way and negotiation. Though some U.S. and Israeli hardliners favor a military solution, negotiation is the cheapest and most reasonable way out, particularly as the U.S. can no longer afford another war in the Middle East against a nation with more than 80 million people.

When challenged with the question of why the U.S. should sign the deal, John Kerry counter-questioned, "Should we fight a war with Iran"? It was certainly a reasonable answer.

What's more, even if the United States really was able to launch a war, it does not mean that the problem could really be solved. War can destroy the facilities, but it cannot take away something in the mind. As for Iran's nuclear program, it is not just physical facilities, but also knowledge in the minds of scientists.

The deal also paved the way for the United States to adjust its policy toward Iran and the Middle East. The U.S. adopted the policy of containing Iran for most of the time since the Islamic revolution and even almost launched a war against Iran after the Iraq War while allying with Saudi Arabia and protecting Israel. But it seems that the U.S. can no longer afford to contain Iran because of the lessons of the Afghanistan and Iraq wars, America's limited strategic resources and Iran's increasing power.

By reaching the deal with Iran, the United States is not only able to keep Iran nuclear issue on a diplomatic track but also to initiate its policy to engage Iran and even seek Iran's assistance in dealing with major regional issues. Engagement might arouse anger and dissatisfaction among Saudis and Israelis against the U.S. in the short term, but in the longer run, the U.S. will be able to manage regional issues through more balanced way.

The deal will also be a rare legacy for Barack Obama's administration. The mid-term election in 2014 resulted in Republican control of both the House and the Senate. As a result, Barack Obama will find it hard to push forward his domestic agenda. A deal with Iran and the détente with Iran in the aftermath of the deal will be another legacy for the administration in foreign policy in addition to normalizing relations with Cuba.

Though questioned and challenged at home, the deal will prove to be an achievement that stands the test of time. Neither Iran, one of the most important regional powers, nor the U.S., the most important global power, can afford to be hostile to the other side after thirty six years. Hostile policy has consumed huge strategic resources on both sides and wasted too many opportunities for cooperation.

The deal is also a big personal achievement for John Kerry, U.S. secretary of state. Kerry regards himself as an expert on Middle East issues. Since being appointed as secretary of state, he has been concentrating his full energy on various Middle East issues. He even used to work on the Palestine-Israel peace process, Syrian issue and the Iran nuclear issue.

As he focused too much on these issues, he has been dubbed as assistant secretary of state on Middle East issues rather than secretary of state taking care of overall American foreign policy.

Despite frustrations in Palestine-Israel negotiation and Syrian issue, the nuclear deal will prove to be worthy of his efforts on Middle East issues.

Besides being a success, the deal is also a big challenge for Barack Obama's administration. The first and the biggest challenge will come from Congress. Though Barack Obama has proved to be able to defeat the rivalry at the negotiating table, he cannot necessarily win over his opponents at home.

He could demonstrate his presidential power by vetoing the decision of Congress after reviewing of the deal for 60 days, but he might not be able to persuade Congress to remove the sanctions on Iran's oil and financial sectors. That is part of the commitments that the United States made in the deal. He could make concessions in other areas in exchange for that, but the concessions would have to be huge. Then what bargaining chip could he use to make that trade?

The second major challenge comes from abroad. As mentioned, the deal has caused tremendous dissatisfaction from Saudi Arabia and Israel. Both countries are still crucial allies of the United States in the region. Barack Obama will have to do something to pacify their anger. Sales of more advanced weapons might be one choice. But it is not known whether Saudi Arabia or Israel would buy them.

Last but not least, the Iran deal also signifies the decline of the United States in the Middle East. The single most influential external power of the U.S. used to be its hard power to push forward its agenda. But this time it had to depend on diplomacy instead of military means to resolve a thorny issue. It even had to give up some of the objectives it had stood for at the very beginning. It might mean something good, but also means that the U.S. is really declining.

Source of documents：China.org.cn