GOP lawmaker says that if his party’s leadership gives in to Obama, they will have forever altered the checks and balances of the U.S. federal government.

On the House floor on Monday, Rep. Tom McClintock (R-CA) argued that President Barack Obama’s activities during the government shutdown over Obamacare are a sign to him that Obama would act nefariously to attack the full faith and credit of the United States of America by taking the country into a default in a debt ceiling crisis if the president does not get everything he wants in negotiations.

“Given the ruthless and vindictive way the shutdown has been handled, I now believe that this president would willfully act to destroy the full faith and credit of the United States unless the Congress acquiesces to all of his demands, at least as long as he sees political advantage in doing so,” McClintock said in a speech on the floor of the House of Representatives. “If the Republicans acquiesce, immediate crisis will quickly vanish, credit markets will calm and public life will return to other matters. But a fundamental element of our Constitution will have been destroyed. The power of the purse will have shifted from the representatives of the people to the executive. The executive bureaucracies will be freed to churn out ever more outlandish regulations with no effective congressional review or check through the purse. A perilous era will have begun in which the president sets spending levels and vetoes any bill falling short of his demands. Whenever a deadline approaches, one house can simply refuse to negotiate with the other until Congress is faced with the Hobson’s choice of a shutdown or a default. The nation’s spending will again dangerously accelerate. The deficit will rapidly widen. And the economic prosperity of the nation will continue to slowly bleed away.”

McClintock said that while the current impasse began “over a collapsing health program,” Obamacare, “it’s now taken on the dimensions of a constitutional crisis.”

“Yesterday in Washington, a group of America’s veterans rose up to take a stand against these unconstitutional usurpations,” McClintock added. “I believe the salvation of our nation now ultimately depends on the American people joining them.”

McClintock argued that the debt ceiling “exists” for a “simple reason.” He said it is there “to ensure that public debt isn’t recklessly piled up without Congress periodically acknowledging it and addressing the spending patterns that are causing it,”

“If the debt limit increase is supposed to be automatic as the president suggests, then there’s really no purpose to it,” he said.

McClintock explained that unlike any of Obama’s predecessors, if Congress does not “unconditionally” raise the debt ceiling, the United States will default on its debt obligations. But McClintock pointed to how the Government Accountability Office (GAO) has “consistently held” that the Secretary of the Treasury, who currently is Jack Lew, a position that reports to the president, has “‘the authority to choose the order in which to pay obligations of the United States’ and to protect the nation’s credit. Such authority is inherent in the 1789 act that established the Treasury Department and entrusted it with ‘the management of the revenue’ and ‘the support of the public credit.'”

McClintock said that given that the nation’s revenues are “more than 10 times our debt payments,” for the Treasury Department and Obama White House to pay “the debt first to prevent a sovereign default is well within the financial ability of the federal government.”

“Indeed, it is a fiscal imperative,” he said, before noting House-passed legislation that would require the payment of the national debt in the case of the lack of a deal over raising the debt ceiling. That measure, McClintock said, “languishes” in the Democratic-controlled Senate under the threat of a veto from President Obama.

“Protecting the sovereign credit by prioritizing payments would mean delaying paying other bills,” McClintock said. “That is also untenable, unthinkable and something much-to-be-avoided. But it would not imperil the nation’s sovereign credit. Only the president can do that.”

McClintock noted how House GOP leadership offered to President Obama a no-strings-attached “clean” 60-day debt ceiling increase, and how Obama refused the offer. He also noted how Senate Republicans offered a six-month clean debt ceiling increase, and how Senate Majority Leader Harry Reid refused that.

“What the president threatens to do would be catastrophic and unprecedented,” McClintock said. “The full faith and credit of the United States is what gives markets the confidence to loan money to the federal government. Even the threat of default, exactly the kind the president is now making, could have dire consequences to a nation that now owes more than its entire economy produces in a year.”

McClintock said that, moving forward, establishment Republicans need to fix their “miscalculations on two key assumptions.”

“First, that the Democrats would negotiate the issues that divide our country; they have not,” McClintock said of such GOP establishment’s false assumptions in these negotiations. “Second, the Democrats would seek to minimize the suffering caused by the impasse; they have not.”

WATCH THE FULL VIDEO OF REP. TOM McCLINTOCK’S SPEECH: