THEY WON’T KNOW WHAT THEY’VE GOT ‘TIL IT’S GONE…. Whether I can relate to it or not, I understand many of the frustrations the Democratic base is feeling. I can understand the disappointments about some of the successes not including provisions the base wanted to see, and I can understand the number of issues Dems wanted to see tackled in this Congress that weren’t addressed.

What I can’t understand is dismissing the significance of the milestone accomplishments of 2009 and 2010. Greg Sargent this afternoon flagged a poll that I just found painful.

What if the Dem base’s lack of enthusiasm is rooted in the fact that Dems aren’t even aware of how much Congress has accomplished in the last two years?

A new poll from Pew and National Journal contains a really striking finding: Only one third of Democrats think this Congress has achieved more than other recent Congresses. Meanwhile, 60 percent of Dems think it has accomplished the same or less.

All of the usual caveats apply — I haven’t yet taken a close look at the methodology; I haven’t seen similar results elsewhere; it’s just one poll; etc. But having said all of that, to deny the accomplishments of this Congress is a serious mistake.

Specifically, 20% of respondents in this poll said Congress had accomplished more this year than in recent Congresses, 36% said less had been done, while 37% saw it as about average. Among Democrats, the results were better, but not much — 33% said this Congress scored well on accomplishments, 23% said less was done, and 37% said this Congress accomplished about the same amount.

Putting aside whether one approved of the policy breakthroughs, this poll result makes it seem as if much of the public simply doesn’t realize that the policy breakthroughs were unusual.

I don’t expect the public to have an extensive knowledge of federal policymaking history, but I at least hoped Americans would realize the scope of recent accomplishments. We are, after all, talking about a two-year span in which Congress passed and the president signed the Affordable Care Act, the Recovery Act, Wall Street reform, student loan reform, Lily Ledbetter Fair Pay Act, new regulation of the credit card industry, new regulation of the tobacco industry, a national service bill, expanded stem-cell research, the Hate Crimes Prevention Act, the most sweeping land-protection act in 15 years, etc. Policymakers might yet add to this list in the lame-duck session.

Some of these efforts have been years in the making. In the case of health care reform, politicians have been talking about a major overhaul for a full century, but it took this Congress and this president to get it done.

This Congress has been about as many accomplishments as recent Congresses? Seriously?

Again, maybe you agree with these accomplishments, or maybe you think they were mistakes. That’s not the point here. What’s worth acknowledging is that we haven’t seen this many accomplishments, on this scale, in decades. Norm Ornstein has characterized this Congress as being the most productive in 45 years. Rachel Maddow recently went further, observing, “The last time any president did this much in office, booze was illegal. If you believe in policy, if you believe in government that addresses problems, cheers to that.”

Whether rank-and-file Democrats realize it or not, this is why the Republicans’ right-wing base is as animated this year as is it — it’s not because Dems are pushing a lot of key progressive priorities that have languished for years; it’s because Dems are passing a lot of key progressive priorities that have languished for years.

Greg concluded, “Maybe this speaks to an enormous Dem failure to communicate their successes. Or maybe it’s another sign of how bloated expectations were amid the euphoria of Obama’s win. Or perhaps the sense of just how monumental our problems are — and the fact that Dems secured such large Congressional majorities — led rank and file Dems to expect truly historic, paradigm shifting levels of leadership. Either way, these numbers shed fascinating new light on the enthusiasm gap problem. Just wow.”

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.