WASHINGTON -- Unintentionally so or politically motivated, Prime Minister Benjamin Netanyahu enters Congress on Tuesday set to deliver the address of his career.

In the shadow of Winston Churchill— in his mind, anyway— Netanyahu will deliver his third speech to a joint meeting, which will also be his third speech focused on Iran.

March 17, Israel's national elections, may play a role in the prime minister's positioning in Washington. But nearly two decades of concern over Iran and its nuclear ambitions brings Netanyahu to this moment, where he addresses the American people over a threat he believes demands a public debate before diplomats reach a political framework agreement on the program, possibly by the end of March.

He will be careful not to detail classified US intelligence in the speech. But towing the line, he will lay out new information before Congress in order to drive home the nature of the threat he perceives. 

Speaking with The Jerusalem Post on Monday, one senior Obama administration official said that US President Barack Obama has no plans to respond directly to Netanyahu's speech.

The official said the focus, instead, is on reaching a detail-oriented, technical solution to the nuclear issue. The administration has laid out concrete proposals to Tehran, the official asserted, speaking with a sense of umbrage at Netanyahu's decision to criticize the effort without putting forth what the White House considers to be viable counterproposals.

Nor will the president watch Netanyahu. Instead, he will be in the White House Situation Room on a conference call with the leaders of Germany, France, the United Kingdom and the European Union - all parties to the negotiations currently under way in Geneva, where they have already presented Iran with a proposal.

60 Democratic members of Congress are skipping the joint meeting, but that does not mean those who are attending are doing so enthusiastically. Watch carefully for moments when Democratic leadership sits, stands and applauds— a key barometer of any joint gathering.

The proposal on the table would restrict Iran's program strictly for at least ten years, preventing them from coming within one year of obtaining the materials necessary for a nuclear weapon. Key to the deal, officials say, is an intrusive inspections and verification system. Over time, sanctions on Iran would be lifted.

Netanyahu is expected to outline aspects of the Geneva proposal that he considers unacceptable to Israel— the wisdom of a sunset clause on a deal, which would ease restrictions on Iran after a finite period; the likelihood of Iranian compliance throughout its duration; and the world's Plan B should Iran kick out inspectors, only a year away from a nuclear bomb.

The speech itself may not change the course of the negotiations. But Senator Bob Corker (R-Tennessee), chairman of the Senate Foreign Relations Committee, as well as Senator Robert Menendez (D-New Jersey) and several other colleagues seek legislation that would require congressional approval of enforcement of any future deal.

Support for such a bill may rest on the outcome of this speech. Without lobbying for specific legislation against the president, expect Netanyahu to allude to the role of Congress as a co-equal branch of government with a key role on Iran policy. 

Netanyahu may go as far as to say that, given the unique threat Iran poses to the Jewish people, Israel finds itself cornered but unbound by a future nuclear pact. When he refers to Israel's experience acting alone in its defense, he is suggesting a willingness to sabotage a deal with unilateral Israeli military force.

Whether such a strike is still within Israel's capabilities is questionable. But Netanyahu's fear of an emboldened Iran is so grave— and his trust in Obama so lacking— he may find himself entertaining the extreme. More than any other moment, this inflection point reflects his fears and his vision of what Zionist leadership requires.