The Iran agreement is now a done deal. And the instinctive response is to pretend that things can go back to how they were before. Once the nuclear accord is implemented, Mr. Obama said a few weeks ago, he expects “pretty quick” improvements in American-Israeli relations. In Israel, members and opponents of Mr. Netanyahu’s coalition argue that restoring the relations with Washington is the most important next step.

But maybe Israel shouldn’t strive to bring relations back to their exact former state. This crisis is an opportunity to reduce our excessive reliance on Washington and think creatively about a way to achieve our goals even in the rare cases when they stand in contradiction to American policy.

Improving Israel’s ties with emerging powers, such as India, is key to advancing such a cause. Cooperation between the two countries on defense and other matters is getting closer, and there are other states in Asia with which Israel can cautiously find common cause. China is an obvious choice, provided that relations with it are managed in a way that would not be detrimental to Israel’s ties with America.

Strengthening regional cooperation with countries like Saudi Arabia, which also opposed the Iran deal, is another way forward. The agreement with Iran endangers Israel but also presents an opportunity: Many countries in the Middle East also see Iran as a threat. They might finally decide that the time has come for them to cooperate with Israel. (Relations between Israel and Egypt are already improving because of mutual threats from Islamist groups.)

Nor can Israel dismiss its relations with Europe. Many European powers are highly critical of certain Israeli policies — especially toward the Palestinians. But Europe is nearby and an important commercial partner. Israel should creatively develop possible alliances with like-minded European countries, especially in Eastern Europe and the Mediterranean region. And it should strive to independently improve its relations with Western European states, rather then relying on Washing-ton to counterbalance their biases whenever there is trouble.

It’s no coincidence that Israel was more entrepreneurial in its foreign relations when its ties with America were weaker. It bought arms from Czechoslovakia, when Washington wouldn’t sell Israel weapons, and it conspired with France, leaving America in the dark before the 1956 war. It was close to Iran and to Turkey, independently of Washington; it collaborated with South Africa on matters the United States did not want to discuss; and it even went to Oslo to negotiate with the Palestinians without approval from the White House.

For the foreseeable future, the United States will likely remain Israel’s main ally. But it must not be Israel’s only ally.

It can no longer be the “no-plan-B” type of ally or a “no daylight” ally. The Obama administration now believes that the United States has certain critical interests, and Mr. Netanyahu’s government believes that Israel has certain critical interests — and they are not the same. As a result, the policies of the two countries are no longer compatible on several key issues. For Israel, finding a way to supplement its ties with Washington is therefore not a luxury; it’s an urgent necessity.