It’s hard to pin down the shape of a future administration’s foreign policy, especially so when the administration is still in the late larval stages, as Joe Biden’s currently is. Still, a picture is emerging: We’re aware of the core views of the aspiring commander in chief, hear the tenor of the rhetoric emerging from among his chief advisers, and know this group’s judgment on the legacy of the administration it hopes to replace. One challenge to the clarity of that picture is that Biden himself has been scattershot on foreign policy over a lengthy career in government: Biden served on the Senate Foreign Relations Committee for more than a quarter-century until he became Barack Obama’s vice president in 2009. Without cherry-picking contradictions from a foreign policy record that spans nearly five decades of government service, it’s impossible not to notice that Biden has pivoted frequently and seems to lack core convictions beyond what has agitated him most recently. Biden was hawkish on Bosnia after a trip there in 1993, co-sponsoring a bill that ultimately forced President Bill Clinton to take action in 1995 to stem the bloodshed of the Yugoslav Wars. And he supported Clinton’s bombing of Serbia during the Kosovo war in 1999 that helped give birth to the Albanian-majority nation. But he was skittish on George H.W. Bush’s intervention in Iraq, while supporting George W. Bush’s decision to invade a bit more...