As soon as Democrats captured the House of Representatives last week, the incoming committee chairs began promising vigorous oversight of the Trump administration. They plan to hold hearings, investigate wrongdoing, and propose new legislation. Foreign policy experts welcomed the chance to reverse congressional neglect of international affairs as the leading Democrats on the House Armed Services, Foreign Affairs, and Intelligence Committees vowed greater scrutiny of national security.

Yet the reality is likely to fall short of the hype. Over the last few decades, political and institutional barriers have sprung up that could block any serious review of foreign policy and defense decisions. Despite a daunting array of problems around the world, the 2018 elections turned on domestic issues and disapproval of President Donald Trump. International relations barely registered as a problem in opinion polls, a fact that may diminish enthusiasm for major inquiries. Moreover, the House defense and foreign policy committees will have to compete with other committees for media attention. And they can expect rival inquiries from Republicans in the Senate and vigorous attacks from a president adept at distracting the public and the press from substance.

Oversight is essential to holding the executive branch accountable and educating the public. Good legislation depends on thoughtful review of how governmental programs have performed, and congressional committees are required by statute to review federal agencies. They have staff and subpoena powers to help them do it, but lawmakers tend to prioritize passing bills over conducting oversight. House members usually do more than senators to monitor agency activities and generally step up their investigations when there is a divided government. The potential for heightened monitoring is there, and with legislative gridlock the likely result of continued Republican control of the Senate and the White House, Democrats expect to reap political rewards by focusing on the administration’s actions.

Many commentators point to the flurry of investigations that followed the Democratic capture of Congress in 2006 as a template for action in the next two years. Back then, public anxiety about the conduct of the Iraq war produced a wave election and stimulated fresh oversight. Democratic-led committees in both the House and the Senate were more vigorous overseers of national security than their GOP predecessors, as shown in the figures below. They conducted hard-hitting inquiries, for example, into the neglect of wounded soldiers at Walter Reed Army Medical Center, although long-standing norms of bipartisan support for the military diverted many inquiries into closed sessions invisible to the public.

The numbers, however, indicate that overall activity in both chambers was low compared with that during previous wars. Even the short and relatively bloodless Gulf War, in 1991, generated more hearings than the Iraq war did in the 2007–09 Congress.

Senate National Security Hearing Days, 1947–2014. Linda Fowler

House National Security Hearing Days, 1947–2014. Linda Fowler

If the Democratic Congress at the end of the George W. Bush administration provides a less than satisfactory model for foreign policy oversight, the GOP-controlled Congresses during the Obama administration offer an even worse one. Today’s committee leaders should look to their GOP predecessors only for lessons about what they shouldn’t do.

Like the Democrats today, Republican lawmakers back then loathed the sitting president and disagreed vehemently with his national security decisions. After Republicans took control of the House in 2010, the prospect for oversight grew. Yet the panel in the figure for the House above shows a substantial decline in hearing days for Armed Services and Foreign Affairs. During that period, President Barack Obama ordered several shifts in U.S. strategy in Afghanistan and Iraq, but the committees’ reactions were relatively muted. Instead, their efforts skewed heavily toward imposing political costs on the Obama administration, particularly with repeated inquiries into the Benghazi attacks in 2012.

The Republicans’ failure reveals something important, however, about the institutional problems that impede responsible oversight. In an era of extreme partisan polarization, congressional committees in both chambers have lost prestige and ceded influence to party leaders. The committees retain important responsibilities but matter less to individual members’ careers than they did in the past. Republicans have made matters worse by imposing term limits on committee chairs, devaluing policy expertise, and cutting committee staff. Congress is frequently criticized for passing few bills and missing its own budget deadlines. Yet most people aren’t aware of the parallel decline of congressional committees, which now hold fewer hearings than at almost any point since World War II.

From a peak in the 1970s, the frequency of all public hearings declined steadily until the mid-1990s. In the House, the number of days featuring public hearings stabilized at roughly 1,000 per year over the past two decades, while the rate in the Senate continued to fall. The result is limited time for oversight.

Days of public Congressional hearings, 1947–2017. Source: Policy Agendas Project. Note that data for 2017 are incomplete. Linda Fowler

Hidden within these trends is an even more important statistic. The average number of days per hearing topic has declined from several days to just one, which constrains members’ ability to assess the scope of an issue, offer possible solutions, or bring the public into the conversation. Today, even in the vital realm of national security, hearings seldom last more than four or five hours and too often feature academics, think tank advocates, or scripted bureaucrats and military personnel. The press, which has dramatically reduced its coverage of Congress generally and the national security committees specifically, now devotes little space to hearings, giving presidents almost no reason to heed them.

In their eagerness to put the Trump administration in the dock, Democrats should remember what leads to successful oversight. The best investigations start with a problem that Congress has the authority to fix. They engage authoritative, trusted witnesses to tell compelling stories that people will see as relevant to their lives. Productive oversight hearings play out over weeks or months, so they require patience and discipline from members of Congress, who must resist the impulse to chase after every headline. The Church Committee investigations of the CIA in the 1970s and the Goldwater review of military procurement in the 1980s both showed Congress at its best. As a result, they had measurable effects on public discourse and led to major reforms, which is why we remember them today.

Voters have handed the incoming Democratic committee chairs a major opportunity. Now they must decide what they will do with it. They could use their gavels solely to discredit Trump and his national security policies. Perhaps doing so would improve their electoral prospects in 2020. There is, however, a greater task, if they are up to it: restoring responsible public discourse about the United States’ role in the world. The political and media environment will be working against them, but if Democrats can use congressional hearings to offer an alternative to Trumpism, they will revive, at least in part, the United States’ tattered system of checks and balances.