The Manafort indictment is bad for Trump. The Papadopoulos plea might be worse.

Normally, the indictment of a former campaign manager for multiple counts of fraud would overshadow almost all other bad news a president faces. But Donald Trump is no ordinary president. As the Associated Press reports, an unsealed indictment this morning revealed that George Papadopoulos, former aide on the Trump campaign, “pleaded guilty on Oct. 5 to one count of lying to FBI agents about the nature of his interactions with ‘foreign nationals’ who he thought had close connections to senior Russian government officials.”

The Papadopoulos plea is even more important than the Manafort indictment on a number of counts. First, because it is a plea, it suggests that Papadopoulos has flipped and is cooperating with special counsel Robert Mueller’s investigation. The Manafort indictment, by contrast, suggests that Manafort is not yet cooperating, since one major reason for bringing an indictment could be to put pressure on Manafort.

Second, the Papadopoulos plea directly links a Trump campaign official with attempts to make a deal with the Russian government. Papadopoulos had emailed a high-ranking campaign official with a subject heading “New message from Russia.” In it, he proposed to make an “off the record” trip to Russia to meet with Russian foreign ministry officials “in the interest of Mr. Trump and the campaign.”

Furthermore, Papadopoulos in April 2016 learned from a Kremlin-linked “professor” that the Russians had “dirt” on Hillary Clinton, including “thousands of emails.” Months later, hacked emails from the Democratic National Committee were leaked.

In sum, a member of Trump’s campaign has pled guilty and provided evidence that the campaign did collude or attempt to collude with Russia. That cuts to the heart of the Mueller investigation—and it means that the president should be in very deep trouble.