The United States is likely to reach $40 trillion in national debt this week, a milestone arriving several months ahead of schedule and drawing sharp warnings from fiscal hawks, including a former Republican senator.

The Washington Post reported on Tuesday that the debt is likely to hit the $40 trillion mark partly as a result of President Donald Trump's invalidated tariffs. The new borrowing, the paper noted, has arrived at a "perilous moment," with inflation and rising geopolitical risk driving investors away from U.S. government bonds — the securities that anchor global finance as the benchmark asset against which other debt is priced, and whose demand is closely watched as a gauge of confidence in U.S. fiscal management.

Speaking to CNN's Erica Hill, former Sen. Pat Toomey of Pennsylvania warned that the country's debt has become nearly unmanageable, posing significant economic headwinds for future generations. Toomey, a Republican, represented Pennsylvania in the Senate from 2011 to 2023 after earlier service in the House and a career in finance.

"Republicans are in power right now. Is fiscal responsibility at this point a thing of the past?" Hill asked.

Toomey's answer was unambiguous.

"Well, if you look at what's actually happened legislatively, yes," Toomey said. "But it's a thing of the future one way or another, because we can't continue on this path of huge deficits, [and] mounting debt. At some point, something's going to give, and it could be very ugly."

The Post's reporting suggests the rising debt could tee up another fight in Congress next year over raising the debt ceiling, the statutory cap on how much the Treasury may borrow to cover obligations already approved by lawmakers. Congress has raised or suspended the limit repeatedly over the decades, and past standoffs have rattled financial markets, including a 2011 episode that prompted Standard & Poor's to strip the United States of its triple-A credit rating. The current cap was reinstated in January 2025 after the suspension agreed to in the 2023 Fiscal Responsibility Act expired, and the Treasury has relied on accounting maneuvers known as "extraordinary measures" since then to keep paying the government's bills — a stopgap that delays the deadline for congressional action but cannot substitute for it.

"For the past quarter-century, the national debt has grown under both parties, through the tax cuts of the George W. Bush era, the wars in Iraq and Afghanistan, the Great Recession, the 2017 Trump tax cuts and the nearly $2 trillion Biden administration initiative to prop up the economy during the coronavirus pandemic," the Post noted. "Trump pledged during his first campaign in 2016 to eliminate the debt within eight years; instead, it has doubled since he first took office."

The Treasury Department tracks and publishes the total public debt outstanding on a daily basis; the gross figure combines debt held by the public with intragovernmental holdings. The debt first crossed $30 trillion in early 2022 and passed $35 trillion in mid-2024, milestones that came alongside steadily rising interest costs on federal borrowing and annual deficits running close to $2 trillion. Net interest has grown into one of the largest single line items in the federal budget — in fiscal 2024 it cost the government more than it spent on national defense, according to Treasury data — and the Congressional Budget Office projects that debt held by the public will continue to climb as a share of the economy over the coming decade.

This article is based on reporting by Raw Story and The Washington Post.