Israeli Prime Minister Benjamin Netanyahu's decisive victory in Tuesday's election was impressive. His cynical campaign was not.

Netanyahu's election may mean new strains for the already-frayed U.S.-Israel relationship, but it is important for the United States — and imperative for Israel — that the alliance endure despite the deepening differences in policy and personality between Netanyahu and President Obama.

Most troubling was Netanyahu's election-eve renunciation of his previous position on Palestinian statehood. This clarifying and disappointing event may have shored up short-term support, but in the long term it likely will cost Israel legitimacy in international institutions and world capitals, where Palestinian Authority President Mahmoud Abbas may press his case.

It's not that the prospects for a peace process were good, especially given that the Palestinians themselves are riven with divisions between Abbas' Fatah faction, considered more moderate, and Hamas, which Israel, the United States, the United Kingdom and several other countries rightly consider a terrorist group. But Netanyahu's hard line — and his histrionics on Election Day about a surge in Arab voting, which is something he should encourage of Israeli citizens — may make it harder for the Obama administration to be a buffer against the burgeoning boycott, divestment and sanctions movement that threatens to isolate Israel. The United States is often a lonely, and even lone, bulwark against such unconstructive actions, and Netanyahu just made diplomatic efforts to forestall them more difficult.

Obama must continue to defend America's key ally. But he also should continue with the bipartisan two-state policy, which was begun under President George W. Bush. It remains the right moral and geopolitical policy.

The vote may make Netanyahu an even more outspoken opponent of Obama's policy on Iran. He already broke protocol and undermined Obama with his speech to Congress. That stunt, coupled with a highly controversial and counterproductive "open letter" from 47 irresponsible Republican senators to the theocracy that rules Iran, has made diplomacy more difficult.

Benjamin Netanyahu

The talks over Iran's potential nuclear weapons program are multilateral, not bilateral, negotiations. International unity is essential if sanctions are to succeed. If efforts to derail the deal are successful, the United States may be blamed, Iran might get sanctions relief without making sufficient compromises on its nuclear potential and soon there may be calls for military action. This catastrophic outcome can be best avoided if Obama sticks to his strategy of committing to global diplomacy.

Netanyahu still has to build a coalition to govern, and these negotiations may create an opportunity for him to soften positions that threaten to further erode the alliance. The U.S.-Israel relationship will never be perfect, but in the wake of Netanyahu's victory, it's in the best interests of both countries for it to improve.