Trump (copy) (copy)

President Donald Trump walks to the Oval Office with Sen. Lindsey Graham, R-S.C. File/Evan Vucci/AP

Critics have seized on an apparent difference on Iran between President Trump and Sen. Lindsey Graham to suggest that Mr. Trump is weak or that Sen. Graham is a warmonger.

Yes, Mr. Trump is taking a softer line on Iran’s provocations for now while Sen. Graham is urging “decisive action.” But both agree that Iran is not getting Mr. Trump’s message, and that it must be reinforced. The message is that Iran cannot provoke the United States into war or escape the continuing economic pain of U.S. sanctions as a way of evading the need to change its aggressive and destabilizing actions.

The issue is how to respond to the Sept. 14 attack that temporarily shut down half of Saudi oil exports and led to a spike in world oil prices. Evidence presented by Saudi Arabia says the attack originated on Iranian soil.

Mr. Trump on Friday will be presented with a range of options including low-level military attacks on Iran’s weapons launchers and storage and perhaps on Iran’s oil facilities. Cyberattack options are another possibility, along with measures targeting Iran’s main military force, the Revolutionary Guard, which is deployed outside Iran in support of its Middle East operations, according to The New York Times.

Similar options were discussed Wednesday on Fox News by retired Army Gen. Jack Keane, who argued that force must be used that is “robust enough to impose costs” that will deter further Iranian efforts to disrupt world oil markets.

Iran needs to be shown that it has taken a losing tack, but there must be no rush to action. These should be preliminary discussions meant for Iranian ears.

The first priority must be strengthening Saudi defenses against further attacks, building up the Arab coalition opposing Iran’s meddling in the Middle East and strengthening diplomatic support for any possible military response to Iranian actions. That will take time.

Commenting on the Sept. 14 attack, Sen. Graham, R-S.C., issued a news release Tuesday saying, in reference to an earlier Iranian attack, “The measured response by President Trump regarding the shooting down of an American drone was clearly seen by the Iranian regime as a sign of weakness. ... [I]t is imperative we take decisive action to deter further aggression by” Iran.

Get a weekly recap of South Carolina opinion and analysis from The Post and Courier in your inbox on Monday evenings.

Sen. Graham on Wednesday agreed with Secretary of State Mike Pompeo in calling the attack “an act of war” against Saudi Arabia. President Trump has not gone that far yet.

Mr. Graham wisely urged strengthening the alliance between the United States and Arab nations led by Saudi Arabia and bringing Iran before the United Nations. That is a good diplomatic strategy. It clearly is time to urgently seek allied support against what is almost certainly Iran’s serious attack on another nation and on the global economy.

Beyond that, there remains the question of  “decisive action” called for by Sen. Graham and Gen. Keane. Only the president can make that decision, but he needs to know what sort of international support he could obtain and weigh the broader consequences of any military action. If it comes to military action, the United States must have strong international support and involve forces from a number of nations, including Saudi Arabia, the victim of the Sept. 14 attack.

There is likely to be more provocation by Iran in coming weeks and months. The way to meet it is not to lash out or to retreat from the Middle East, but to firmly deter any escalation, in part by having adequate force on the ground in the form of an Arab coalition and in part by military and diplomatic actions that make Iran aware of the possible larger costs. Sen. Graham is doing his part by raising the issue.