With the fight in Congress over President Barack Obama’s unilateral extension of legal status to millions of illegal immigrants in the form of a battle over funding for the Department of Homeland Security ongoing, it is clear that Republicans are losing. Despite winning their largest majorities in both chambers of Congress since World War II not three months ago, the GOP seems reluctant to engage in a fight they picked over the implementation of this overreach by the executive.

And while Republicans decline to make their case to the public as to why they believe the president has exceeded his constitutional authority, Democrats are busily defining the Republican Party as – you guessed it – cruel and heartless monsters.

“They seem to dislike the idea of supporting homeland security,” said Sen. Chuck Schumer (D-NY) recently. “They dislike dreamers more than they dislike ISIS.”

This crude and baseless slander is the heart of the Democratic attack on the GOP’s efforts to forestall the implementation of the president’s executive actions.

It is baseless because the Department of Homeland Security cannot be shut down. At least, not as a result of the course Republicans are pursuing. As I’ve written previously, the Democratic Party’s messaging against the fight over DHS funding is perfectly contradictory. Democrats simultaneously claim that that fee-funded agency within DHS that Republicans are targeting is fully financed, and Obama’s executive actions cannot be stopped even if the president were to miraculously sign a de-funding proposal passed by Congress. At the same time, Democrats insist that the GOP wants to shut down American national security; an unlikely prospect given that 85 percent of DHS continued to operate even during the government shutdown of 2013.

Schumer’s attack is slanderous because it suggests that Republicans are more concerned about preventing illegal immigrants from working in the United States than they are about the prospect of Islamist terrorism. If the Republicans were leveling these same charges at Democrats under different circumstances, the press would rush to defend the honor of both the president’s party and its members. Republicans can expect no such courtesy from the media, so is incumbent upon members of the GOP to defend themselves. Thus far, we have seen precious little spine from the congressional GOP when it comes to prosecuting this fight over DHS funding.

Instead, the party seems terrified by Democratic messaging – propagated by the party’s members in Congress and advanced by a sympathetic media. They are deathly afraid, it appears, that Schumer’s line of attack will take hold in the minds of average Americans. Let’s be clear: While it is unsubstantiated and grotesquely opportunistic, Schumer’s line is a powerful one. It is easy to comprehend and it advances the notion that Republicans are eager to shut down government functions, even essential ones, in order to advance a parochial and callous anti-immigrant (or, worse, anti-Hispanic) agenda.

But Schumer’s rhetoric is hollow, and the burden of making that case should not fall entirely on conservative media outlets.

Republicans in Congress should know that, by failing to litigate this fight over the president’s executive actions on immigration, they are inviting an internal civil war. Many conservatives were dissatisfied with the House majority’s advance of “CROmnibus,” but some were mollified by the prospect of waging the fight over Obama’s executive actions on more favorable ground. If the congressional GOP declines to engage in this funding fight, even if it only results in a presidential veto, they will invite the wrath of an enemy far more threatening than the political press. They will have sparked a real conflict between the party’s leaders and its grassroots supporters, and they will deserve it.