Opinion writer

Negotiators in Vienna had announced the Iran nuclear deal only an hour earlier, but Sen. Lindsey Graham of South Carolina, a Republican presidential candidate, was already on the airwaves denouncing it.

“You have created a possible death sentence for Israel,” he declared on MSNBC’s “Morning Joe.”

“This is a virtual declaration of war against Sunni Arabs,” he said.

“This is the most dangerous, irresponsible step I have ever seen in the history of watching the Mideast. Barack Obama, John Kerry, have been dangerously naive,” he added.

Tough stuff. But had Graham actually seen the deal?

“No,” he admitted, when host Mika Brzezinski asked him.

“I don’t understand,” another host, Mike Barnicle, told Graham, “how you can be so certain without having read the deal yet.”

“Because I have been to the Mideast enough to know,” Graham replied.

Of course Graham hadn’t read the deal — he couldn’t have. More than 100 pages of text and annexes went online about 6:30 a.m., and the European Union site where it was posted soon crashed. The Obama administration won’t get all the supplemental material to Congress for up to five days, and then there will be a battery of briefings.

But Graham and his congressional colleagues are not reserving judgment until they know the facts. This is, perhaps, to be expected after 47 GOP senators sent a letter to Iran’s ayatollahs trying to block an agreement even before there was one. Sen. Tom Cotton (R-Ark.), author of that letter, called the new deal “a terrible, dangerous mistake.”

This is legislating by reflex — a mass knee-jerk by the Republican majority in Congress. Those who howled “read the bill” during the health-care debate couldn’t be bothered to read the nuclear agreement before sounding off.

They are perfectly entitled to oppose the deal (though opponents would need two-thirds of both chambers to disrupt the pact). But the reflexive reaction suggests they are against it because President Obama is for it — and that they oppose the very notion of negotiating with Iran.

Whatever one thinks of the agreement, the alternative was not necessarily a “better deal,” as Israeli Prime Minister Benjamin Netanyahu said. There may be war with Iran, or, more likely, the Europeans, who do think this is a good deal, will drop their sanctions even if the United States doesn’t — thereby leaving Iran relatively free to pursue its nuclear ambitions.

Such considerations got lost in the reflexive response, kicked off by Netanyahu, who proclaimed an hour before the deal was announced that, based on “early reports,” it was “a historic mistake.”

From there, it was all leaping, little looking. “Israel blasts Iran deal as ‘dark day in history,’ ” Sen. John Cornyn (R-Tex.) tweeted, just as Obama went on TV to announce the agreement. As Obama spoke, Rep. Randy Weber (R-Tex.) tweeted: “What part of ‘Death to America’ did this Administration not understand?”

These were among the first of a flurry of lawmakers’ tweets in the early minutes of the Iran deal’s life, saying that Obama “paves way for a nuclear Iran and gives Tehran millions to fund their global terror” and that he is “encouraging Iran’s nuclear capabilities.” A previously scheduled House hearing opened at 10 a.m. with witness Joe Lieberman, the hawkish former Democratic senator, calling the pact “a bad deal for America, a bad deal for Iran’s neighbors in the Middle East, and a bad deal for the world.”

Some Republicans were more responsible, saying they would “Look forward to studying details” (Arizona Sen. Jeff Flake), even if they would view them with “deep skepticism” (Tennessee Sen. Bob Corker, chairman of the Foreign Relations Committee).

Those vying to lead the GOP, alas, were not so patient. Mike Huckabee said the hour-old agreement “empowers an evil Iranian regime to carry out its threat to ‘wipe Israel off the map.’ ” Marco Rubio and Scott Walker suggested future presidents would ditch the deal, and Ted Cruz called it a “staggeringly bad deal” and “a fundamental betrayal” of U.S. and Israeli security.

Graham, who days earlier admitted the interim nuclear agreement “worked better than I thought,” toured the cable-news studios, telling CNN the deal empowers “religious Nazis.”

By about 9 a.m., House Speaker John Boehner (R-Ohio) and Senate Majority Leader Mitch McConnell (R-Ky.) had both reached conclusions. Boehner said that Obama “abandoned his own goals,” that the deal would put Iran on “a break-out threshold to produce a nuclear bomb,” and that it would “only embolden Iran — the world’s largest sponsor of terror.”

“It sounds,” a reporter later said to Boehner, “like you’ve already rejected it.”

“I want to review all the facts,” the speaker replied.

Verdict first — then the facts.

Twitter: @Milbank

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