The Tuesday night speaking lineup for the Democratic National Convention was always intended as a muscular contrast on foreign policy and diplomatic integrity, presented to viewers under the evening’s unsubtle theme: "Leadership Matters.”

There were two former commanders-in-chief, Bill Clinton and Jimmy Carter, and a former chairman of the Joint Chiefs turned chief diplomat: Colin Powell. There was Sally Yates, the former deputy attorney general who famously warned the White House in early 2017 that Michael Flynn, President Donald Trump’s first national security adviser, had lied about his Russian contacts.

And John Kerry, the former secretary of state who negotiated the Iran deal that Trump decimated, was called in to validate Joe Biden, the Democratic nominee and Kerry’s former Senate peer, as a steady-handed statesman for precarious times.