Washington at the beginning of the Obama era has the feel of a city that has just been liberated from foreign occupation, or of a person who just snapped out of an inexplicable psychotic episode. The paranoia of the Bush days has passed. The world is no longer divided into children of light and children of darkness.

The standard assessment says that after his return to power, Benjamin Netanyahu will have a tense time when he visits Washington - just as he did during his first term when he faced a president who demanded that he advance a peace process. That assessment isn't quite right - because this time, Netanyahu is likely to have an even more tension-fraught time than he did in the 90s. In his new term, he won't be able to count on Congress as a counterweight to the administration in his relations with America.

During his first visit to Washington as prime minister in 1996, Netanyahu spoke before Congress to repeated applause. The part of his speech praising deregulation and tax cuts helped him by warming the hearts of the Republican majority. Today that economic approach is correctly seen as the cause of a worldwide disaster, and the Republicans are a defeated minority. Economic spin won't help Netanyahu build a responsible image.

More important, Congress' attitude toward the Arab-Israeli conflict has begun to shift. The conservative line of AIPAC, the veteran pro-Israel lobby, is no longer the only understanding of how to support Israel. The principle of two states for two peoples has become conventional wisdom on the Hill, as someone with a close knowledge of Congressional discussions of foreign policy recently told me. That's the same principle that Netanyahu refused to endorse during his talks with Tzipi Livni.

Rep. Gary Ackerman provided a clear sign of the change last month. Ackerman, a Jewish Democrat from New York, is chairman of House of Representatives' Subcommittee on the Middle East and South Asia. In his opening statement at a subcommittee hearing, he warned of a downward spiral leading to the point where "the two-state solution to the Israeli-Palestinian conflict is finally rendered impossible." He added, "The downward pressure comes from terrorism and the march of settlements and outposts, from the firing of rockets and the perpetration of settler pogroms." Ackerman hasn't been known in the past as a dove, notes another source who keeps close track of Israel-related activity in Congress. Today Ackerman isn't worried that criticizing Israel's policies in the territories will sound heretical.

To that, add Senate Foreign Relations Committee Chairman John Kerry's visit to Gaza - a symbolic breach of the siege of the Strip. Kerry was the first member of Congress to visit Gaza since 2000. Afterward, when he asked Ehud Barak to explain why Israel was blocking shipments of pasta to the Strip, he didn't worry about being labeled anti-Israel if his intervention were publicized. And in just two days last week, Sen. Dianne Feinstein of California signed more than 30 of her colleagues on to a letter to Secretary of State Hillary Clinton, urging her to expand efforts to bring Israeli-Palestinian peace.

One reason for the change is that AIPAC no longer has a monopoly on concern for Israel. J Street, the new, dovish pro-Israel lobby, pressed senators to sign Feinstein's letter. Members of Congress and their staffers have attended recent briefings held by the new lobby.

This isn't a sharp shift. When Barack Obama demands that Netanyahu freeze settlement construction or resume peace negotiations, a certain amount of protest might be heard from Congress, but it will be muffled protest, a low grumbling. Netanyahu's marketing skills and his fluent English won't rescue him from the basic contradiction between his positions and those of the new administration. In liberated Washington, neither will Congress save him.