You don't seem to understand the significance of intent. At all.
Your opinions are also curiously contradictory. Jaime was more practical than Selmy, but he also didn't hold the virtue of honor in high regard, and that's why he was willing to inherit dishonor in order to commit a dishonor (killing his king) to spare so many lives. That doesn't mean Selmy was "self-serving". He adhered to the code of honor of a knight. He didn't see it as his place to decide when the royals he served were making the right or wrong decision. And it's understandable why that became the code, philosophically; because if you think that way, at any point, a mutiny is threatened by a whim. It's a slippery slope. How do you identify when the moment arrives that a threshold has been crossed, and now is the moment justifying treason? Do you think we are any different even without our monarchs? The Secret Service doesn't forcibly oppose the President even if some in their ranks might believe the President is carrying out genocidal campaigns abroad with his foreign policy. That isn't their place, it isn't their right. Many across the world would already argue that moment has been reached, and would love to see our President assassinated. That's true any time of the day, any day of the year, every year that marches on. The knight is shield & sword, not a crown.
Ned, similarly, was willing to inherit dishonor, but in his case, it wasn't to protect the realm, but the illegitimate child of his sister. That was one of those genius flourishes by Martin. Ned and Jaime suffer a similarity of fate despite being so dissimilar otherwise in character, motivation, and circumstance.
Finally, what does "fuck her and her promise" mean? Does that mean Ned should sacrifice the child? Because that's what you're proposing. Infanticide to quell the chaos of a contested realm. That's what they would have done. They'd kill the child. Are you too naive to understand that? Robert couldn't have let Jon survive. Furthermore, I don't understand why you're blaming Ned for the consequences of her choice which led to Robert's Rebellion as "self-serving". How is he responsible for Lyanna and Rhaegar's choice? Revealing the truth wouldn't have compromised his honor, but hers, and Rhaegar's. And it wouldn't have spared a war because all the royal houses would still have been entangled in a scandal with a Mad King on the throne to resolve it when his own brother was involved in it. Baratheon was still wronged, and the Martells now would have known they had been wronged, too. If the King was going to serve rational justice, he wouldn't have murdered the Stark lords when he thought his brother had kidnapped Lyanna. He was never going to hold his brother accountable. War was inevitable. Ned was wise enough to know he didn't know how everyone would react to the situation either way.
I don't understand how anyone could construe anything Ned did to be self-serving.
