Sens. Mitt Romney and Lindsey Graham. Photo: Tom Brenner/Getty Images

Sen. Lindsey Graham (R-S.C.) said President Trump should consider attacking Iranian oil refineries in retaliation for the drone strikes on Saudi oil plants, while Sen. Mitt Romney (R-Utah) said direct U.S. intervention would be "a grave mistake," per Bloomberg.

The big picture: Opinions on U.S. involvement are split since the attack against Saudi Arabia didn't occur on U.S. soil, endanger American lives or happen in a country that is a partner in a defense treaty with the U.S.

What they're saying: Brian Hook, the State Department's special representative for Iran, told congressional staffers that "Saudis consider it to be 'their 9/11,'" reports the Washington Post.

  • "The comparison to the terrorist attacks, ... in which 15 of the 19 hijackers came from Saudi Arabia, rankled several staffers," writes the Post.

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