Ronald Brownstein, Columnist

Congress Is Addicted to Megabills — Despite Their Risks

Both parties have forgotten, or rejected, the advice of Thomas Jefferson, who wrote in 1808 “that great innovations should not be forced on a slender majority.”

Congratulations, for now.

Photographer: Alex Wong/Getty Images

Extraordinarily narrow and unstable House and Senate majorities have become routine in modern American politics. The frantic, final maneuvering last week before Congress approved President Donald Trump’s One Big Beautiful Bill Act shows why that’s likely to persist for some time. And that means business, local governments, non-profits and ordinary Americans need to buckle up for more hairpin turns in national policy that make it almost impossible to plan for the long term.

Political parity has become a defining feature of our times. Neither party has won a House majority greater than ten seats in each of the past three congressional sessions. That hasn’t happened since the formation of the modern party system in 1828. Likewise, one or the other party has reached 55 or more Senate seats in only three of the 13 congressional sessions since 2000, compared to 17 of the final 20 sessions of the 20th century.