We have yet to reach the three-month anniversary of Donald Trump's inauguration, yet a death watch has already started in Washington over the White House tenure of Trump advisor and chief strategist Stephen Bannon. This development was precipitated by a single publicly-confirmed fact—Bannon's abrupt removal from the National Security Council—but a host of on-background quotes in the press have attested to Bannon's falling star, further fueling the intrigue of the week.
Bannon, a former Hollywood producer who migrated to the Trump campaign last August from the bare-fanged conservative website Breitbart, has the kind of unconventional biography for a political aide that invites particular fascination—as does his cultivation of a shadowy, Master of Darkness persona. Gossip about who's in and who's out in the scene around Trump also understandably attracts interest, and Bannon's identification with the ethno-nationalist "alt-right" movement aligned with Trump ensures that his departure, if and when it comes, will have a real symbolic meaning. But it's unlikely to affect the political trajectory of the Trump presidency to any significant degree.
Substantively, Bannon differs from the average Republican political advisor by emphasizing economically populist messages and policies on jobs, trade, and domestic infrastructure, combined with an even more aggressive opposition than other Republicans to immigration (both legal and illegal) and international alliances. This combination of positions, along with a more general "anti-establishment" attitude, has been collectively viewed as defining Trumpism as distinct from regular American conservatism.
Since taking office, however, Trump has addressed immigration fitfully and the other issues hardly at all. He has turned responsibility for setting his presidency's legislative agenda over to the Republican congressional leadership, which chose to pursue deregulation, ACA repeal (now in indefinite limbo), and comprehensive tax reform while making decidedly unenthusiastic murmurs about tackling an infrastructure bill or funding a wall along the Mexican border. It's difficult to detect Bannon's hand in most of the events of the past two months, after he took the lead in devising the "travel ban" executive order that was soon blocked in federal court (as was its replacement). Even last week's airstrike in Syria seems inconsistent with Bannon's worldview, and reports indicate that it occurred over his opposition.
Redefining the Republican Party, restructuring the international order, achieving the "deconstruction of the administrative state": these are exceedingly ambitious aims that are likely to frustrate even a competent and dedicated presidential administration. They certainly can't be accomplished, even partially, between rounds of golf or during the commercial breaks of "Fox and Friends"—or by delegating the real work to Congress or mid-level White House staff.
There was probably a time, in the immediate wake of the election when Washington was in a state of paralytic shock, when Trump and Bannon could have imposed substantial change on the political system, if they had acted quickly and effectively. But that window is now closed, probably for the rest of Trump's presidency. Poll numbers have slumped, mistakes have added up, key executive-branch positions have gone unfilled, and other political actors have perceived—and in some cases been told outright—that the new president cares more about "wins" and favorable publicity than the content of the policies implemented by his administration. This last admission is particularly damaging, since it signals to other elites that they should not take Trump's stated positions seriously—and gives them every reason to insist on policy demands of their own in exchange for political support (a tactic adopted by the House Freedom Caucus on the issue of health care).
Trump may rebound politically in the months and years to come, but it's hard to see how the larger ambitions of the "America First" policy program can be fulfilled, at least in the domestic sphere—and therefore, unclear what particular value Bannon provides by sticking around. (His removal from the NSC seems to answer the question of what future influence Bannon will have on foreign policy, even if he remains in the White House.)
At the same time, Trump's not necessarily much better off without him. An experienced, realistic, politically astute chief advisor is something this presidency needs desperately. By all accounts, however, the main rival to Bannon for Trump's favor is the president's son-in-law Jared Kushner, who may not represent an improvement on any of these scores and whose family ties give him more protection, and less restriction, than Bannon was ever likely to have. Trump may be merely trading frustration in the pursuit of one set of objectives for similar ineffectiveness in the fulfillment of other, equally implausible goals.
Bannon's marginalization is likely to be widely cheered in Washington, and it will be natural for critics to treat him as a personification of Trump's rocky first months in office—the Mack McLarty of the 21st century. But this view ignores the importance of the pre-existing dysfunction within the congressional Republican Party, as well as the degree to which Trump's sliding political standing also reflects his swift abandonment of economic populism to embrace Paul Ryan's agenda of tax cuts for the wealthy and benefit cuts for the rest. It's not only Bannon's alt-right that has caused Trump grief; the plain old regular right is, for him, just as much of a problem.