The following contains major spoilers for Shang-Chi and the Ten Rings #3, available now from Marvel Comics.
When Shang-Chi inherited his father's place as the Supreme Commander of the Five Weapons Society, his relationships with his fellow Avengers were immediately called into question. Apart from being the man in charge of a sprawling, cult-like organization, that Shang-Chi's new empire didn't roll over in the face of Earth's Mightiest Heroes made many wonders whether the Master of Kung Fu had become a villain. Now that he has also inherited the legendary Ten Rings, it isn't just the Avengers who are worried about where Shang-Chi is headed, and MI-6 have just gone from his oldest allies to his worst enemies.
After his old friends from MI-6 called on him for help, Shang-Chi joined agents Clive Reston and Leiko Wu for what seemed like an otherwise ordinary, high-stakes affair. Despite their years of fighting alongside one another, not to mention Shang-Chi and Leiko's prior romance, the entire mission turned out to be a ploy to separate the Master of Kung Fu from his eponymous armaments. As seen in the pages of Shang-Chi and the Ten Rings #3 (by Gene Luen Yang, Marcus To, Erick Arciniega, and VC's Travis Lanham), however, not even MI-6's best can contain the power of the Ten Rings. When this forces Shang-Chi to corral and reclaim the Ten Rings on his own, it proves just how out of their element his former friends were all along.
Shang-Chi's Relationship With Marvel's MI-6
British super spies may not seem like typical Marvel fare, but they have been an essential part of Shang-Chi's story ever since his introduction all the way back in 1973's Special Marvel Edition #15 (by Steve Englehart and Jim Starlin). It was MI-6's own Sir Denis Nayland Smith who first offered Shang-Chi a way out from under his father's shadow, with the likes of Clive and Leiko making their respective debuts in the years that followed. Though Shang-Chi's fellow agents never attained the household name status he has, their influence on him as a hero cannot be understated, which makes it all the more painful when he has to disown them.
That the people who helped him find himself as a hero have betrayed him is shocking enough, but that they decided to do so based on their own worst assumptions is simply more than Shang-Chi is willing to deal with any longer. By the time he has reclaimed the Ten Rings, he is ready to officially disavow any and all relationships he had with MI-6 or its operatives. Although this is more than understandable considering the personal damage that has been done, it still might not be enough of a guilt trip to convince MI-6 to back down.
Shang-Chi Could be Facing a War
Assuming MI-6 does launch another attempt to "safeguard" the Ten Rings, they won't have Shang-Chi there to protect them from the impossible power of the ancient artifacts they do not understand. Rather, they will find themselves up against a powerful new enemy who has grown beyond their well-practiced field tactics and surprise maneuvers. MI-6 would also end up staring down the full might of the Five Weapons Society, while the fact that the latter is fractured could work out to the further detriment of the Crown.
While attacks on the Five Weapons Society by MI-6 can be brushed aside as necessary engagements, the former striking back could only ever be considered an act of war. Should that come to pass, it is hard to imagine any scenario in which the Five Weapons Society wouldn't emerge victorious. Between their sheer numbers at home and those under the purview of Shang-Chi's siblings across the globe, the Five Weapons Society is more than capable of dismantling any Earthly opponents that come their way. Then again, going to war with England would very likely mean going to war with the rest of the world's superheroes as well, and that is the one fight Shang-Chi has no hope of every coming back from.