Julian Zelizer is a professor of history and public affairs at Princeton University, and author, with Kevin Kruse, of the new book "Fault Lines: A History of the United States Since 1974." The opinions expressed in this commentary are his own. View more opinion at CNN.

(CNN) The Democratic leaders struck on a great slogan when they started talking about the "Trump Shutdown" during the famous televised Oval Office meeting with President Trump last month. House Speaker Nancy Pelosi and Senate Minority Leader Chuck Schumer warned Trump that the blame for a government shutdown would fall on him, but the President happily accepted the responsibility and said, "I am proud to shut down the government for border security."

Julian Zelizer

Both Pelosi and Schumer have since repeated the phrase "Trump Shutdown," but it's not actually the most accurate description of what's going on. This is really the Republican Shutdown, or maybe the Grand Old Party's Dysfunctional Moment, and it's vital that we be clear about what is going on.

Republicans could end this shutdown if they really wanted to do so. Before the last session of Congress ended, the Senate passed a bill to fund the government until early February, which did not include any funding for Trump's border wall. The bill was poised to pass in the House, and Senate Republicans, after having lunch with Vice President Mike Pence, said they were confident Trump would sign the spending bill. But Trump then said he would refuse to accept a stopgap measure that did not include funds for his wall, and while the House managed to pass a new bill that included the $5 billion in border wall funding, it was dead on arrival in the Senate.

If Senate Republicans decided to pass the original version of the bill before Trump intervened, it would likely pass in the House and place immense pressure on the President to end the longest government shutdown in US history. And should he veto the legislation, two-thirds of the House and Senate could override it. Republicans would have to show where they stand. Would they support the President and the ongoing shutdown or work with Democrats to reopen government?

When Democrats tried to bring forth a vote to reopen the government on Thursday, Sen. Mitch McConnell promptly shut them down . McConnell is stalling any progress and the main reason that President Trump can continue to hold the government hostage in order to force Democrats into accepting his demands on border wall funding is because Senate Republicans are letting him get away with it.

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