As the Senate grinds through a grueling amendment marathon on President Donald J. Trump’s landmark One Big Beautiful Bill (OBBB), the President took to Truth Social early Tuesday to deliver a stark warning: Failure to pass the legislation could trigger the largest tax hike in American history.

In a post aimed directly at Republicans wavering under pressure from Democrats and special interests, Trump wrote:

“Republicans, the One Big Beautiful Bill, perhaps the greatest and most important of its kind in history, gives the largest Tax Cuts and Border Security ever, Jobs by the Millions, Military/Vets increases, and so much more. The failure to pass means a whopping 68% Tax increase, the largest in history!!!”

The message landed amid an extended “vote-a-rama” in the Senate, as lawmakers filed a flurry of last-minute amendments to stall or reshape the bill. The legislation—which delivers $4.5 trillion in historic tax relief, permanent Trump-era tax cuts, and deep slashes to bloated entitlement programs—has become a battle for the soul of the GOP.

Senate Republicans hold a narrow majority and cannot afford more than three defections. Already, Sen. Thom Tillis (R-NC) and Sen. Rand Paul (R-KY) have signaled opposition. Tillis, under intense fire from President Trump for obstructing key provisions of the bill, announced he would not seek reelection after the president threatened to back a primary challenger.

Senate Majority Leader John Thune (R-SD) said Republicans are “figuring out how to get to the end game,” but insiders suggest the final votes may not come until dawn.

While the One Big Beautiful Bill eliminates billions in wasteful green subsidies and expands border security funding by $350 billion, not everyone on the right is happy—most notably Elon Musk, the billionaire tech mogul and former head of Trump’s Department of Government Efficiency (DOGE).

Musk, whose companies once benefited handsomely from green energy tax credits, erupted in anger over the bill’s rollback of EV subsidies—even threatening to start a new third party.

“It is obvious with the insane spending of this bill, which increases the debt ceiling by a record FIVE TRILLION DOLLARS, that we live in a one-party country – the PORKY PIG PARTY!! Time for a new political party that actually cares about the people,” Musk posted on X.

President Trump swiftly responded, putting the billionaire on notice.

“Elon Musk knew, long before he so strongly Endorsed me for President, that I was strongly against the EV Mandate. It is ridiculous, and was always a major part of my campaign,” Trump wrote.

“Elon may get more subsidy than any human being in history, by far, and without subsidies, Elon would probably have to close up shop and head back home to South Africa. No more Rocket launches, Satellites, or Electric Car Production, and our Country would save a FORTUNE. Perhaps we should have DOGE take a good, hard, look at this? BIG MONEY TO BE SAVED!!!”

Trump's pointed message underlines the friction between fiscal conservatism and corporate welfare—a rift now playing out in real time.

The One Big Beautiful Bill also includes $1.2 trillion in Medicaid and food stamp reforms, targeting rampant fraud and tightening eligibility to preserve programs for those truly in need. The legislation also boosts deportation funding and cracks down on sanctuary policies by conditioning state reimbursements on federal cooperation.

Despite his prior alignment with Trump, Musk's criticism has taken on a sharper edge in recent days. On Monday, the Tesla and SpaceX CEO publicly floated launching an “America Party” as an alternative to the “uniparty” establishment.

“If this insane spending bill passes, the America Party will be formed the next day,” Musk declared to his 220 million followers on X. “Our country needs an alternative to the Democrat-Republican uniparty so that the people actually have a VOICE.”

While some conservatives appreciate Musk’s free speech advocacy, many are skeptical that a third-party stunt would be anything more than a spoiler effort benefitting Democrats. As one senior Trump adviser told Fox News: “Elon doesn’t like losing a subsidy. That doesn’t make him the voice of the American people.”

What’s clear is this: The One Big Beautiful Bill is a once-in-a-generation opportunity to restore economic liberty, secure the border, and dismantle the deep state’s spending racket. And with Trump leading the charge, the stakes couldn’t be higher.