Biden also nodded to the ongoing impeachment proceedings against Trump, in which the president is accused of abusing his power by attempting to withhold foreign aid, by saying Trump is misusing the nation’s historic commitments to NATO.

“NATO is not a protection racket,” Biden began saying this week, emphasizing the phrase during his multicity “No Malarkey” bus tour of Iowa.

For Biden’s campaign, the new line of NATO-focused attack is designed to hit Trump on a point of potential vulnerability — the president frequently makes statements that other nations are laughing at the United States and has promised he would change that.

The criticism of Trump also reinforces a perceived Biden strength — foreign policy. To reinforce that message, Biden’s campaign unveiled former secretary of State and 2004 Democratic presidential nominee John Kerry’s endorsement.

Winning Kerry’s endorsement just two months before the Iowa caucuses solidifies Biden’s argument that he is the only 2020 candidate with the foreign policy experience necessary for the White House at this moment.

While serving as a Delaware senator, Biden served on the Senate Foreign Relations Committee for three decades, including as chair. As vice president under Barack Obama, Biden took a lead role in developing policy in Afghanistan, Iraq and Ukraine. In endorsing Biden on Thursday, Kerry noted he and Biden served together for 24 years on the Foreign Relations Committee.

“When Chairman Biden became Vice President Biden, he didn’t just hand me a gavel, but a legacy of getting things done with integrity and bipartisanship, and shared experiences on hundreds of thousands of miles traveled together building relationships around the world,” Kerry said in a statement.

Biden’s description of working with world leaders under Obama was a staple of his stump speech in town halls throughout rural Iowa earlier this week.

Biden noted in Emmetsburg that he has met alone with Vladimir Putin. “Not a decent guy. Trying to undo Europe.”

In Algona, Biden noted that North Korean leader Kim Jong Un had taken a verbal shot at him; Biden then mocked Trump’s reaction to the tyrant’s remarks.

“Look what’s happening now, this president is embracing thugs and dictators. Kim Jong Un did say that I'm a rabid dog, I should be beaten to death with a stick. Right afterwards, the president sent him another love letter,” Biden said to laughter.

In an interview on Monday, Biden lamented that foreign policy has not come up enough in the presidential contest and predicted that when the election is over, it will have played a major role in how the electorate decides on its next president.

“It’s not discussed at all in the debates,” Biden said then.

