In this May 4, 2017 photo, President Donald Trump, accompanied by GOP House members, cheer for Speaker of the House Rep. Paul Ryan, R-Wis., after the House pushed through a health care bill, in the Rose Garden of the White House in Washington, D.C. (AP Photo/Evan Vucci)

During the 2016 election, many observers from across the political spectrum saw Donald Trump’s candidacy as a direct challenge to the Republican Party’s ideological orthodoxy. Reporters described Trump as an “insurgent populist” running on a policy platform that “cuts across party lines . . . [and is] anathema to movement conservatives.” From Barack Obama on the left to Bill Kristol on the right, critics described Trump’s brand of politics as fundamentally incompatible with conservative principles and Republican heritage.

But that’s not what we’ve seen so far. Instead of transforming the Republican Party, Trump has assembled the most conservative administration and agenda of any modern president. Analysts overstated Trump’s distance from Republican campaign orthodoxy and expected him to be able to avoid the challenges of leading his party from opposition to governing mode. As a result, they underestimated the resilience of the GOP’s basic character.

Many observers misread the Trump campaign, predicting a political realignment between the parties

Because Trump’s campaign was so superficially unusual, journalists exaggerated its distance from ordinary conservative positions. Like previous Republicans, Trump relied on broad symbolic rhetoric rather than policy specifics. He accused the Democrats of weakness on national security and the mainstream news media of bias. He denounced Obamacare without explaining how he would replace it, proposed large-scale tax cuts, and decried government regulation.

Trump even stood to the right of other Republicans on his signature issue: immigration. He deployed nativist rhetoric and denounced international institutions. That reinvigorated the American right’s tradition of nationalism – and aligned the Republicans with a global trend among far-right parties.

The Washington Post's Philip Rucker, Ashley Parker and David Nakamura look at what President Trump has done over the past six months to fulfill his pledge to build a border wall. (Bastien Inzaurralde/The Washington Post)

Trump’s campaign did deviate from a few conventional Republican positions – particularly on free trade and entitlements. But so had previous conservative populists, like Pat Buchanan. Predictions that Trump’s rise would cause the parties to realign ideologically were overstated.

In fact, Trump is governing like a firm – even far-right conservative

Before the election, we predicted that Trump wouldn’t redefine Republican ideology; rather, the GOP’s stable congressional leadership and infrastructure would change Trump, forcing him to “reconcile his ambitious campaign promises with the realities of governing without alienating conservative ideologues.”

And that’s what has happened. Trump is not trying to redefine party orthodoxy or build coalitions with the Democrats. His executive branch appointments have tilted farther to the ideological right than previous Republican presidents (as did his Supreme Court nomination). Working with the Republican-controlled Congress, his appointees are swiftly reversing Obama-era regulations. Republican leaders have driven the congressional agenda, emphasizing ACA repeal, tax reform, and corporate deregulation rather than Trump’s less conservative campaign proposals like infrastructure spending and expanded parental leave.

Speaking to conservative activists, Feb. 24, President Trump outlined his plans for tax reform, regulatory rollback and strengthening the U.S. military. (Reuters)

Trump’s proposed federal budget endorses deep cuts to many domestic programs, and his positions on social issues – such as his recently-announced decision to ban transgender servicemembers from the military – are just as conservative.

Trump’s distinctive personality continues to dominate headlines. But the president’s personnel and policy choices mostly show how he’s constrained by the broader Republican infrastructure of media, interest group, and activist supporters, who were attracted to his angry denunciations of Obama policies but weren’t interested in a leftward tilt.

Even though some observers saw the recent departure of White House chief of staff Reince Priebus as a sign of Trump’s growing independence from the “Republican establishment,” there’s no reason to think that the president’s frustration with Priebus’s performance is leading him to reconsider the rightward policy direction of his administration.

Here’s why the Republican Party is pulling Trump rightward

 Our recent book, Asymmetric Politics, explains why the GOP cannot easily be diverted from its conservative path. The Republican Party is the agent of an ideological movement — unlike the Democratic Party, which is a social coalition defending the concrete interests of its constituent groups. Democratic politicians work to achieve incremental benefits for a variety of electoral constituencies. But Republican voters, politicians, and activists are motivated instead by adherence to a single ideological doctrine. With Trump’s election, Republicans are continuing their longstanding drive toward a broad rightward shift in policy.

President Trump asked House Republicans if they can "believe" that he's president, while celebrating the passage of the American Health Care Act in the House of Representatives on May 4 at the White House. (The White House)

Republicans’ firm and uncompromising dedication to small-government values can cause big problems for party leaders. The congressional right wing has already shown that it’s willing to oppose health care and budgetary proposals introduced by its own party’s leadership. Disputes among Republicans over how much electoral risk the party should take in order to remain true to conservative principles can be just as difficult to resolve as typical Democratic disagreements over which party constituency should receive the most attention from officeholders.

Many conservative Republican themes – like personal liberty, American nationalism, and moral traditionalism – are quite popular. But the ideology is more appealing than most specific conservative policy positions. As Republicans have discovered during frustrating debates over health care, while “small government” may be an attractive idea, losing government benefits or protections is not – and provokes a backlash.

Why Trump still represents a conservative opportunity

Previous Republican presidents resolved these conflicts by pairing selected conservative priorities with major policy initiatives departing from ideological precepts — even expanding the size and scope of government.

For instance, George W. Bush launched a new federal intervention in public education, No Child Left Behind, which included nationwide standards and testing; regulated the accounting industry; brought back agricultural subsidies; and passed a new prescription drug entitlement. His father George H. W. Bush hiked the minimum wage, raised taxes, increased environmental regulation, and expanded disability rights. Ronald Reagan hiked gas taxes to fund transportation improvements, built major job training programs, and offered amnesty to undocumented immigrants.

But Trump is sticking with a more consistently conservative path and refusing to compromise with the Democratic opposition. In doing so, Trump and his Republican congressional allies are trying to reverse a decades-long trend in which federal policymaking has drifted in a liberal direction no matter which party is in power.

If the Trump administration doesn’t win any major legislative victories while he’s in office, conservatives will surely be quite disappointed. Yet if Trump pursues regulatory retrenchment within the federal bureaucracy while declining to advance any major new legislative expansions of government responsibility, he will still compile the most conservative policy record of any recent administration.

Reporters and pundits like to portray political campaigns as a battle of individual personalities. But elections are mostly a competition between two partisan teams. Many Republican leaders and activists saw Trump’s victory as a rare opportunity to move national policy much farther to the right. Rather than trying to squelch or redirect these ambitions, Trump has staked his presidency on fulfilling them.

Matt Grossmann is director of the Institute for Public Policy and Social Research and associate professor of political science at Michigan State University. Find him on Twitter @mattgrossmann.

David A. Hopkins is associate professor of political science at Boston College and blogs about U.S. politics at Honest Graft.

Together they are the authors of Asymmetric Politics: Ideological Republicans and Group Interest Democrats (Oxford University Press, 2016).