Thunderbolt Ross could replace Norman Osborn in the Captain America: New World Order. The high-profile casting decision surely means he's set to be a major power player in the MCU going forward.
It's reasonable to assume Ross will be an antagonist in Captain America: New World Order. This is in keeping with Ross' portrayal in Spider-Man foe Norman Osborn (the Green Goblin) became one of the most important people in the Marvel Universe.
Thunderbolt Ross Isn't President In Marvel's Secret Invasion Disney+ Series
It's first important to note that Thunderbolt Ross isn't president of the United States in Phase 4. Rather, Skrull sleeper cells, who are conducting a covert invasion in an arc lifted straight from the comics.
In spite of several years of excellent build-up, the Secret Invasion comic book event was actually quite underwhelming; it swiftly devolved into a standard superhero brawl. It's best ed for a major transition of power, with SHIELD boss Maria Hill disgraced and replaced by the hero of the hour, Norman Osborn. Something similar could easily happen in the MCU, with President Ritson's presidency brought to an abrupt end - either because he is a Skrull sleeper agent himself, or because he is targeted and killed by the Skrulls. The first possibility is a fascinating one, given the Skrulls would naturally want to replace high-value targets, but the Secret Invasion trailer hints at the second - with shots of what seems to be a presidential motorcade under attack. Ross could be Ritson's replacement; a most likely scenario is that Ross is already Ritson's vice-president, explaining his post-Sokovia Accords role and also fitting with some of the more dubious U.S. government decisions in Phase 4, typified through the organization called Damage Control.
The MCU's Phase 5 Could Be Thunderbolt Ross' "Dark Reign"
In the comics, Secret Invasion led to one of the most interesting eras in Marvel Comics history. The next year's worth of comics were collectively known as Dark Reign, with almost every book existing in the shadow of Norman Osborn and the superhero teams he commanded, notably the Thunderbolts and the Dark Avengers. The same could be true for Thunderbolt Ross and the MCU's Phase 5 - an idea that fits surprisingly well with the slate. Secret Invasion is confirmed to release in Spring 2023, and the new status quo could then be explored on the big screen in Captain America 4 - perfectly explaining why that film has the title "New World Order." Captain America 4 could feature characters who are resisting Ross' presidency, just as the Avengers resisted Norman Osborn's Dark Reign in the comics.
This story would need to be carefully handled, of course. In the comics, Norman Osborn was simply responsible for policing America's superhumans; the MCU version would literally be dealing with the U.S. president. Thunderbolt Ross would naturally have a democratic mandate, meaning Sam Wilson and his Avengers would be taking a very dangerous decision indeed if they did attempt to overthrow or unseat him in some way. The MCU's Sokovia Accords were essentially an attempt to establish a system of ability for the Avengers, and this would once again raise the thorny question of what right the Avengers have to take unilateral action against the sitting president. The Avengers are treading on dangerous ground.
Looking forward, this would explain why the MCU's Phase 5 is introducing a new team known as the Thunderbolts. Ross has always been interested in the idea of super-soldiers; the novelization of The Incredible Hulk confirms he conducted many before the incident that created the Hulk. It's surely no coincidence the MCU's confirmed Thunderbolts team includes several super-soldiers, just the kind of people Ross would be interested in, and the MCU's team could be given that codename (or nickname) because of the U.S. president who sponsors the program.
How Will Thunderbolt Ross' Dark Reign End?
Ross' ascension would even fit with the build-up to "The Kang Dynasty," confirmed to be the name of the next main Avengers film. This is named after a much-loved Avengers story in which the time-traveling villain Kang the Conqueror took advantage of the Avengers' division and distraction to launch an attack on Earth. The Avengers were preoccupied with a massive number of other threats, and so failed to spot the signs of Kang's coming. It's easy to imagine Ross' "Dark Reign" serving just this kind of role in the MCU's overarching narrative, ensuring the heroes have too much on their minds and fail to organize effectively against a greater enemy.
Such an arc would serve to confirm just how dangerous an enemy Kang the Conqueror really is. If this theory is correct, Thunderbolt Ross is the main villain of Phase 5, but Phase 6 will begin with him being humbled when Kang arrives in force. The various narrative threads running through Phases 4 and 5 would finally be tied together ahead of the Multiverse Saga's final act, ensuring viewers really did take Kang seriously as the MCU's next big bad.
