Oh to be a liberal in America today. In New York City, a Democrat has finally been elected mayor after a 24-year absence from City Hall – and he's a dyed-in-the-wool liberal. Gay marriage is legal in 18 states including, most bizarrely, Utah, one of the most conservative states. The minimum wage is going up around the country and you can even smoke a joint in Colorado. Obamacare, for all its speedbumps over the past few weeks, is the law of the land; the Senate filibuster just took a big hit (and along with it Republican obstructionism); a nuclear deal with Iran is in the works and even Obama is talking about the scourge of income inequality.

Everything, it seems, is coming up roses.

But before progressives start donning their Che Guevera T-shirts and popping their artisanal champagne corks the liberal moment is coming face to face with a difficult reality: conservatives are not going down without a fight.

In fact, just over a year since President Obama was re-elected and it seemed the country was moving in a more progressive direction, Republicans have thwarted much of his agenda and 2014 (as well as 2015 and 2016) promises more of the same.

Immigration reform, which was at the forefront of Obama's re-election bid, is on life support; gun control was blocked in the Senate (and never would have made it through the House anyway). The harsh budget cuts from sequestration remain largely intact as government spending is growing at anaemically low rates.

In the states, the story isn't much better. Twenty-three of the Republican ones have rejected Medicaid expansion, which is leaving more than 5 million Americans on the outside looking in on Obamacare. Emboldened by the Supreme Court decision to overturn a key provision of the Voting Rights Act, states across the country are enacting new and onerous voting restrictions; perhaps worst of all, 2013 was the culmination of a three-year period in which more state restrictions on abortion were enacted than in the entire previous decade.

Quite simply, as the country has taken a giant step forward on a number of progressive goals, it has also taken a major step back. Indeed, in key regards, while Obamacare represents an enormous victory for American progressives and is perhaps the most important piece of social policy in more than four decades, so many liberal priorities remain unfulfilled. And nowhere is that more true than on fiscal policy. While Democrats were finally able to wring tax increases out of the Republican party they've been unable to get conservatives to agree to the sort of government spending that is key not only to the country's economic recovery but to creating new jobs and reducing income inequality.

While New York City's new mayor, Bill de Blasio, ran on a platform of universal pre-kindergarten, the president's own plan along these lines is dead on arrival in Congress. The same is probably true for his $50bn proposal for infrastructure spending. At the end of December, unemployment insurance expired for more than a million Americans and there seems to be little impetus in Congress to restore the funding. This comes only months after the Republicans ruthlessly cut food stamp benefits for poor Americans.

The reason for this is not surprising or new. Republicans have, since Obama took office in 2009, made it their number one goal to obstruct practically every piece of legislation that the president and his party supporters favour. With the Republicans in control of the House of Representatives this year – and for the foreseeable future – that is unlikely to change soon.

This speaks to a larger challenge of American democracy: it was constructed to be a bulwark against progress. Whether it's the three branches of the US government, the separate legislative bodies, the 50 individual state governments or a court system with the power to strike down laws, the number of obstacles in the American political system are far greater than the number of glide points. This has always given conservatives a political advantage – it's much easier to stop reform (or water it down) than it is to enact new laws. If anything, the liberal moment may find its greatest opportunities in the same places it did during the civil rights era – in the court system (as has been the case on the issue of gay marriage). Although even there it may have to wait for President Obama to get his court picks through the Senate before significant progress can be made.

But liberals shouldn't lose all hope. On a range of issues, progressive goals have never been so strongly supported by the American people. From gay marriage and marijuana legalisation to raising the minimum wage, immigration reform, background checks for gun buyers and even the specifics of government spending, public opinion is strongly in their favour. Americans are more supportive of activist government, populist politics and socially liberal policies than at any time in recent memory. In addition, millennials (or those in their 20s and early 30s) are decidedly liberal, even going so far in a recent poll to prefer socialism to capitalism.

The failure of liberalism to enact the types of reforms that are essential to their vision of America does not come from an inability to move popular opinion in their favour – it comes from their failure to find a way around last-gasp conservative rejectionism. But as Republicans have taken increasingly extreme positions on a host of issues – from abortion to taxes and, most damagingly, immigration – they've marginalised themselves and diminished the appeal of conservatism, particularly to young Americans, women and Hispanics (the fastest growing demographic group in the country).

Indeed, the success of Republicans in blocking reform is more of a desperate rearguard action to hold back progress than it is an indication of conservative success or even political ascendancy. If anything, it is making the realisation of the liberal moment that much more likely by making conservatism that much more unpopular.

The problem is: that's not much good for the woman today who is seeking an abortion in a Republican state or the person looking for a job who is about to lose his unemployment benefits or the next victim of gun violence.

In the near term, American politics is likely to look like an extreme version of the gridlock and dysfunction to which Americans have become all too accustomed. The question then is not will liberals get their day in the sun – it's when. Unfortunately for them – and the voters who support them – 2014 is unlikely to be the year it happens.