It may be the most discussed fact about American politics today: The country is deeply polarized. The Republican Party has moved to the right by many measures, and the Democratic Party has moved to the left. Each party sees the other as an existential threat. One consequence of this polarization, politicians and pundits often say, is gridlock in Washington.

But in a country that is supposed to have a gridlocked federal government, the past four years are hard to explain. These years have been arguably the most productive period of Washington bipartisanship in decades.

During the Covid pandemic, Democrats and Republicans in Congress came together to pass emergency responses. Under President Biden, bipartisan majorities have passed major laws on infrastructure and semiconductor chips, as well as laws on veterans’ health, gun violence, the Postal Service, the aviation system, same-sex marriage, anti-Asian hate crimes and the electoral process. On trade, the Biden administration has kept some of the Trump administration’s signature policies and even expanded them.

The trend has continued over the past month, first with the passage of a bipartisan bill to aid Ukraine and other allies and to force a sale of TikTok by its Chinese owner. After the bill’s passage, far-right House Republicans tried to oust Speaker Mike Johnson because he did not block it — and House Democrats voted to save Johnson’s job. There is no precedent for House members of one party to rescue a speaker from the other. Last week, the House advanced another bipartisan bill, on disaster relief, using a rare procedural technique to get around party-line votes.

This flurry of bipartisanship may be surprising, but it is not an accident. It has depended on the emergence of a new form of American centrism.

The very notion of centrism is anathema to many progressives and conservatives, conjuring a mushy moderation. But the new centrism is not always so moderate. Forcing the sale of a popular social app is not exactly timid, nor is confronting China and Russia. The bills to rebuild American infrastructure and strengthen the domestic semiconductor industry are ambitious economic policies.