President  Obama speaks at Henninger High School in Syracuse, N.Y., about his plan to make college more affordable. (Jacquelyn Martin/Associated Press)

The technical defects and volume delays that have stymied the rollout of the federal health insurance exchange in its first month of life are far from the greatest challenges the White House faces in rescuing President Obama’s signature policy achievement. The botched beginning is so dangerous for his legacy precisely because it threatens the foundational hypothesis of Obama’s presidency: that government can work to better Americans’ lives.

A year before the midterm elections, that has Democrats worried that their fates will once again be tied to their president’s health-care reform law — and they’ve seen that movie before.

The debate over the role of government is at the heart of the partisan rancor, both on Capitol Hill and in the United States today. And election results demonstrate just how evenly divided the country has been in recent years. In 2012, 43 percent of voters told exit pollsters that government should do more to solve problems facing the country today; more than 80 percent of those voters backed Obama. About half, 51 percent, said government is doing too much; three-quarters of those voters backed Mitt Romney for president.

In 2010, Republicans rode a wave of negative reaction to perceived government overreach into power. And Obama won election in 2008 by presenting himself as a candidate who could make government work, a contrast from his predecessor, George W. Bush, whose administration had waded into two foreign quagmires, botched the federal response to Hurricane Katrina and presided over the country’s biggest financial collapse and economic recession in 80 years. Obama even cast himself as different from the last Democrat to hold the White House, Bill Clinton, who had declared the end of the era of big government.

The humorist P.J. O’Rourke once said Democrats “are the party that says government will make you smarter, taller, richer, and remove the crabgrass on your lawn. The Republicans are the party that says government doesn’t work and then they get elected and prove it.”

Today, both parties’ coalitions on Capitol Hill are proving him right.

The tea party movement, which sees government as overly intrusive, was as much a reaction to George W. Bush-era expansions of government services like Medicare Part D and the Troubled Asset Relief Program as it was to Obama-era expansions like the stimulus plan and health care reform. Tea party darlings like Sens. Ted Cruz (R-Tex.) and Mike Lee (R-Utah), plus a significant slice of the House Republican Conference, largely drove this year’s government shutdown.

The ascendent coalition on the left, embodied in liberals like Sens. Elizabeth Warren (D-Mass.) and Sherrod Brown (D-Ohio), want government to hold accountable the Wall Street institutions that contributed to the financial collapse.

At times during his presidency, Obama has sounded just like Warren and Brown.

“We know that too much government can stifle competition and deprive us of choice and burden us with debt.  But we’ve also clearly seen the dangers of too little government -– like when a lack of accountability on Wall Street nearly leads to the collapse of our entire economy,” Obama told students in a commencement address at the University of Michigan in May 2010.

“What we should be asking is not whether we need big government or a small government, but how we can create a smarter and better government,” Obama said. “Because in an era of iPods and TiVo, where we have more choices than ever before … government shouldn’t try to dictate your lives. But it should give you the tools you need to succeed.”

Obama’s major policy initiatives have all involved strengthening the role of government in key sectors of American society: The Dodd-Frank financial reforms set out new regulations on Wall Street mega-banks. The stimulus not only provided immediate cash in hopes the government could help the economy rebound, it also created offices like ARPA-E, which invest taxpayer money in advanced energy projects. The health care reform law gave government a more direct role in a huge portion of the national economy. Obama even pressed a proposal, though it ended up going nowhere, to reorganize several Cabinet departments to streamline government operations.

“I do believe that government has a role to play in advancing our common prosperity: by providing stable macroeconomic and financial conditions for sustained growth, by demanding transparency, and by ensuring fair competition in the marketplace,” Obama the candidate said on March 27, 2008. Five years later, as Obama took the oath of office for the second time, he laid out an ambitious agenda for government reform: “Progress does not compel us to settle centuries-long debates about the role of government for all time, but it does require us to act in our time.”

That’s why the disastrous roll-out of the Affordable Care Act is such a political threat, not only to Obama, but to his party. When the HealthCare.gov Web site launched, then promptly crashed, government didn’t give the governed the tools they needed to succeed.

Democratic strategists who will fight to defend their incumbents on Capitol Hill are privately — and increasingly publicly — aghast. The breakdown in communication between the White House and the Department of Health and Human Services that led to launching a Web site that didn’t work has already helped Republicans paper over much of the negative feelings the shutdown had generated; a Quinnipiac University poll published this week showed the two parties at parity in the generic Congressional ballot.

A Web site can be repaired. The problem Democrats truly worry about is that even today, three years after Obama signed the Affordable Care Act into law, the White House has not been able to adequately explain to Americans exactly why they should support the law. That inability to communicate, from a president whose communications skills are seen as one of his greatest assets, was on full display at a press conference on Thursday, when Obama took the blame for his signature accomplishment’s rough debut.

“I understand why folks are frustrated.  I would be, too. Because sometimes people look at what’s taking place in Washington, and they say, ‘Not enough is getting done that helps me with my life,’” Obama said Thursday. “And regardless of what Congress does, ultimately, I’m the President of the United States, and they expect me to do something about it.”

To have any chance at recapturing control of the House of Representatives, Democrats must ride a wave of voter anger at the GOP. The Republican path to a Senate majority is less far-fetched, but still difficult in the absence of a friendly wind at their backs. Polling has so far showed no national wave developing.

But Democrats have felt the bitter backlash against the Affordable Care Act before, when it cost them the House in 2010. If voter anger builds and helps Republicans win seats next year — in the House or the Senate — it will be because the fundamental promise of the Democratic Party, that government can work in ways that private industry can’t, will have fallen short.