Why was the diplomatic problem solved by Obama for decades?

　　First, the balance of power of the international landscape has brought urgency to the problem brought by the parties concerned. The United States has become increasingly aware of the difficulty of maintaining global leadership, and in turning to more of the smart power, the legitimacy of its own actions and the international appeal, and the search for multilateralism. While Cuba and Iran have abundant resources, they have been slow in economic development due to foreign policy reasons. It should be said that the situation is changing and the parties are more aware of what they really want.

　　The second is the Obama administration's pragmatic approach to diplomacy. As President Obama took office, he inherited a badly damaged U.S. foreign policy. Mr Obama knows that his predecessor's hard-line, military priorities have put American diplomacy in a passive position, and the excessive use of force has weakened America's global image and leadership. Therefore, the key words of foreign policy in its first term are "withdrawal", withdrawal from Iraq and Afghanistan, and moderate strategic contraction. The key word for foreign policy in the second term should be "talk", which should be negotiated first and avoid direct military intervention, especially on ground troops, which is evident on the Syrian issue. Although criticized as weak, this has resulted in the settlement of two issues, Cuba and Iran. < / div >

　　Three is Mr Obama's personal element. Obama was born at grass roots, and his childhood's ups and downs had a subtle influence on his later character. He was cautious, but not decisive, and his execution was slightly inadequate. And his political career is less than that of his predecessors, George h.w. bush, Bill Clinton, George w. bush, and other top federal officials, as lawyers and senators. It was his weakness, but in a way it was his strength: it was safe to listen, tolerate and disagree. In foreign policy, he avoided the use of force and emphasized the importance of negotiations.