The first 100 days of Donald Trump's presidency have been chaotic and unpredictable. Reporters who covered it recount the events that dominated the news. (Alice Li,Jayne Orenstein,Julio Negron/The Washington Post)

In early 1933, Franklin D. Roosevelt launched the now-famous goal of accomplishing as much as possible in his first 100 days. And his performance was amazing. He did some things on his own — declaring an emergency shutdown of the banking system, abandoning the gold standard.

But political historians especially remember the legislative binge. The new FDR administration joined Congress to pass major legislation in the areas of banking, securities, agriculture, public works, conservation, work relief and river-valley development, along with the capstone National Industrial Recovery Act. (Actually, that binge took 105 days.)

But FDR’s rush has been the exception, not the rule. On the question of whether dramatic legislation has gotten passed during a president’s first 100 days, two factors are worth taking up. Let’s look at them in turn.

Does the president’s party have a congressional majority?

This is an obvious consideration, although it hasn’t made as much difference as one might think.

Since the 1930s, newly elected presidents who have had congressional majorities of their parties have not enjoyed much legislative success during their first 100 days. Only one enactment stands out as particularly important — President Barack Obama’s stimulus legislation, the American Recovery and Reinvestment Act of 2009 (ARRA), designed to get the country out of the Great Recession. Dwight D. Eisenhower didn’t undertake a major legislative program until his second year in office. John F. Kennedy signed some second-order enactments just after his 100th day, but his party’s top legislative aims in civil rights, Medicare and education went nowhere until after his assassination. Jimmy Carter signed a much-tattered version of his energy plan on his 659th day. Bill Clinton signed his controversial budget on his 203rd day. George W. Bush signed his tax cut on his 139th day.

The record is unsurprisingly lean for newly elected presidents facing an opposition party in at least one legislative chamber. Richard Nixon and George H.W. Bush got little done during their first 100 days. Ronald Reagan signed his budget and tax-cut bills, the major components of the “Reagan Revolution,” on his 206th day.

Is there a national emergency or some other spur to action?

Roosevelt took office with a triple whammy of conditions that made the era legislatively exceptional. After three years of the Great Depression, the 1932 election was charged with urgency — and gave Roosevelt a real mandate to do something. The same election gave the Democrats an immense surge in congressional seats, delivering a majority big enough for them to pursue many ideologically appealing projects that they would have wanted to pursue anyway, crisis or no crisis. And just as Roosevelt took office in March 1933, the banking system was in the midst of a rapid collapse, with governors declaring emergency statewide bank closures to prevent panicky depositors from withdrawing all the institutions’ funds, a situation that demanded immediate action.

Generally speaking, emergencies and other riveting events are what spur fast, consequential legislative action. Often they map at least partly onto new presidents and party seat surges. The 9/11 terrorist attacks prompted the USA Patriot Act (no election connection there). The Lehman Brothers collapse that precipitated the 2008 Wall Street crash resulted in two big emergency enactments — George W. Bush’s October 2008 Troubled Asset Relief Program, or TARP bailout, and Obama’s February 2009 ARRA. Chiefly through ARRA, the United States led the world in fiscal stimulus (as share of GDP) in 2008-2009. And the Democrats now gifted with larger post-election congressional majorities stocked ARRA with many of their spending aspirations, rendering it in one assessment a “new New Deal” all by itself.

Reagan fits this pattern even though his legislative drives extended beyond 100 days. He had similar boosts from an economic sense of emergency and an associated Republican landslide, not to mention an early attempt on his life. He won the presidency in 1980, which brought the worst election-year economy since World War II. Slow growth, inflation and unemployment were dogging the economy. “Tax bracket creep” was spooking many voters, as an inflating currency automatically elevated them into brackets where they had to pay higher rates.

In addition to winning the presidency, the Republicans gained seats in the House and captured control of the Senate. Sold as routes to economic “recovery,” the ensuing Reagan legislative drives brought historic cuts in tax rates as well as cutbacks in a great many domestic programs as the Republicans used their power to pursue many conservative policy objectives. Within two months of Reagan’s inauguration, he was shot in an assassination attempt, an event that seems to have given a boost to his policy drives.

Lyndon B. Johnson is another president with dramatic legislative accomplishments early in his tenure — and who also took office at a time of tremendous national urgency. But he was not freshly elected. He took office immediately upon John F. Kennedy’s assassination in 1963, which traumatized the nation.

Meanwhile, in the South, mass civil rights demonstrations — in Birmingham, Ala., in 1963, and in Selma, Ala., in 1965 — were being met with violent police responses that were televised nationally, transfixing the country. Johnson drew on that well of sentiment to push through the landmark Civil Rights Act, which dismantled Jim Crow, and the Economic Opportunity Act, which launched his War on Poverty, before the election of 1964. That general sense of political urgency poured into the election, resulting in a historic Democratic seat surge that delivered, among many other things, Medicare in 1965.

Trump’s situation is different.

The problem for today’s Republicans is that the social and economic context is relatively calm. There is no recession, bank crisis, terrorist attack or war. An election by itself is not enough. A 100-days legislative binge would have been astonishing.

Trump’s goals — such as tax reform, trade, infrastructure, health care and immigration, are not short-fuse topics. Major changes on these issues require months of congressional fussing. Eisenhower won his tax reform in his second year; Reagan won it in his sixth year. On the infrastructure front, an interest of President Trump, Eisenhower won authorization of the Saint Lawrence Seaway in his second year, the Interstate Highway System in his fourth year.

Of course, if emergencies arise, any of these subjects could take on a new urgency. For instance, a cascade of insurance company exits from the ACA’s state exchanges could bring voter pressure for action. Then, we might see something like the bipartisan agreement behind the 2008 TARP bailout.

Trump’s first 100 days have yielded no major new laws. That is not the whole story.

As happened with Roosevelt, Trump’s executive directives are stacking up. And there is a peculiar congressional front. Where the processes are a simple yes or no and filibustering is banned, Congress can act quickly. Hence the approval of Trump’s Supreme Court nominee, Neil M. Gorsuch, and the surprising use of the Congressional Review Act of 1996 to cancel Obama’s regulations on the environment and other matters.

But in eras with no background crisis, it might be time to retire the expectation that any new president will go on a first-100-days lawmaking binge.

David R. Mayhew is Sterling Professor of Political Science Emeritus at Yale University, and author of “The Imprint of Congress” (2017).