Controversial. Chaotic. But not a do-nothing Congress.

The 115th Congress is going out with a bang – but not the celebratory kind.

Instead it is a deafening noise of shutdown drama and alarm bells over national security that is drowning out the accomplishments of the last two years. Republican Senate majority leader Mitch McConnell describes this Congress as the most successful – from a “right-of-center” perspective – in decades.

The Kentuckian readily itemizes GOP wins: a tax cut for corporations and individuals, regulatory rollbacks, and a record number of judicial appointments, including two Supreme Court justices.

As sometimes happens in a lame-duck session when a deadline looms, a flurry of bipartisan legislation also passed, from the most significant criminal-justice reform in years to a farm bill and #MeToo sexual harassment legislation applying to Congress itself.

“There wasn’t a lot of legislation, but it was big and it was significant, and like many Congresses, it was all crowded toward the end,” says former Senate historian Don Ritchie.

But that's hard to notice when politics is roiled like an angry ocean, amid the unconventional presidency of Donald Trump.

Conservative talk-show hosts and right-wing House Republicans mutinied over a short-term budget deal worked out by the leaders of both parties. The deal would have avoided a partial government shutdown over the holidays by extending current government funding through Feb. 8.

But the extension had no new money for a border wall, arguably President Trump’s top campaign promise, and so the right-wing rebelled – as did the president – causing senators who had already left town for such far-flung states as Hawaii to return quickly to Washington.

On top of that came the unexpected announcement by Trump that he is pulling US troops out of Syria because he says the war against the terrorist group ISIS has been won. That prompted the resignation Thursday of Defense Secretary James Mattis, who openly cited his disagreements with the commander-in-chief. Republicans, Democrats, and America’s allies sounded klaxon alarms at this sudden turn of events. Even the taciturn Mr. McConnell said he was “particularly distressed” by the resignation.

In November, voters repudiated unified Republican control in Washington, handing the House to Democrats. It marked the end of one of those rare opportunities that a party has when it controls both ends of Pennsylvania Avenue.

“The thing that I am struck by is how short-lived unified party control has been” in America’s history, says Sarah Binder, a congressional expert at the Brookings Institution think tank in Washington.

Democratic Presidents Obama and Clinton enjoyed it in their first two years, before voters changed their minds. Republican President George W. Bush had it in the middle of his eight-year presidency. One could argue an “almost” case for President Reagan, whose 1980 election brought the first GOP-controlled chamber – the Senate – since 1953. While he faced a Democratic House, he found support among conservative “boll weevil” Democrats.

But divided control is more the norm, with Americans rejecting “overreach” by one party in power, or the public simply shifting directions or wanting change.

Historian Ritchie grants McConnell his definition of success in this Congress, but points out that Reagan’s first two years were “surprisingly productive,” including a major tax cut. What probably puts this Congress over the top in terms of a conservative agenda are the record numbers of court appointees, says the historian.

While the public focuses on the Supreme Court, and the confirmation battle over Brett Kavanaugh certainly had its undivided attention, the high court decides only 100 cases a year, points out Prof. Carl Tobias, at the University of Richmond School of Law in Virginia. The Trump administration has focused like a laser on the federal appellate courts, which decide nearly all of the cases in their regions, he says. The Senate has confirmed a record 30 such judges, and in the next Congress, Americans can expect “at least as conservative, if not more conservative” judges because Republicans will control more seats.

One distinction of this Congress has been the further erosion of Senate rules and the heavy reliance on rarely used procedures that put the minority party at a severe disadvantage. Indeed, it was through these changes that Senate Republicans were able to cope with their very slim majority to score their marquee achievements: judges, the tax bill, the negating of the individual health insurance mandate (though not Obamacare itself), and regulatory rollbacks.

On Friday, the president demanded that Republicans also fell another Senate rule, the legislative filibuster. That requires that essentially all legislation meet a 60-vote threshold in order to pass. Doing away with it would allow the president to get his $5.7 billion for a wall, passed Thursday night by a majority in the GOP-controlled House. But McConnell and many Republican senators are adamant about keeping it out of concern that they will get steamrolled when their time in the minority comes.

Bipartisanship surged toward the end of this Congress, particularly with the passage in both chambers of the “First Step Act,” which aims to reduce recidivism in the federal prison system and lower the number of prisoners by changing sentencing laws. Lawmakers in both parties had been working on this for years, and it was greatly helped by a big push from the president’s son-in-law, Jared Kushner.

“We shouldn’t forget that even with the discord, bipartisan bills got through,” says John Fortier of the Bipartisan Policy Center, which puts out a quarterly “Healthy Congress Index.” He names opioid legislation and funding for child healthcare as examples.

On the other hand, Democrats were angry that the president, who signed a bipartisan farm bill this week, plans to revive a work requirement for food stamps by using the regulatory powers of the executive branch. It was only by dropping a work-for-assistance provision that the two parties were able to agree on the bill in the first place.

The partisanship, internal GOP division, and presidential unpredictability that so characterized this Congress limited its potential, observers say, pointing to missed opportunities.

Republicans could not coalesce around a “repeal and replace” of the Affordable Care Act – nor could the parties come together to fix its flaws. On the wall, the president had an opportunity to back a bipartisan bill that provided $25 billion for border security, including a wall, as well as a fix for young immigrant “Dreamers” – but decided to side with immigration hardliners in the Senate and his administration instead. In the end the bipartisan bill had the most votes; the president’s bill, the fewest. After the Parkland shootings, he seemed willing to buck the National Rifle Association on background checks, then changed his mind.

New to Congress was a tweeting, “outsider” president who puts a premium on disruption and who is inexperienced with governing. His base loves it, but it has caused deep consternation on the Hill.

When a Trump about-face shifted the budget talk from “deal” to “no deal” late this week, Sen. Ron Johnson (R) of Wisconsin offered, wryly: “Who knows, this could all change in 30 minutes.” 

“I don’t think this is a Congress that any of its members would really want to live through again,” says Ritchie. “It wasn’t the happiest of times for either party. A lot of it had to do with an unpredictable president that caused a lot of tension. Everybody would like a return to greater stability. Greater predictability.”