The partisan divide tends to suffuse every facet of American public life, and foreign policy is no exception. Most Democratic and Republican elites, and many of their voters, believe that the country and the entire world order are under siege from a foreign menace that demands aggressive countermeasures, if not outright war. Probably the only thing the two camps disagree about is whether that menace is Russia or China.

In other words, the major dividing line isn’t between advocates of peace and restraint, on one hand, and escalation and hawkism, on the other. It’s between hawks who emphasize different zones of geopolitical rivalry.

Progressives are increasingly obsessed with the Russian threat, putting them at odds with the historic left’s foreign-policy orientation. Sen. Bernie Sanders, for instance, began his career urging Ronald Reagan to make peace with a Soviet Union that had invaded Afghanistan. In an earlier era, the Vermont socialist routinely decried “endless wars” and the military-industrial complex fueling them. Yet working within a Democratic Party in which anti-Russian hawkishness has become an inviolable principle, Sanders has been lockstep with President Biden on the Ukraine war, even criticizing House progressives for timidly urging diplomacy last year.

“While conservatives are … wary of escalating over Ukraine, they are as hawkish as ever.”