Individuals with handguns are no match for a modern army. It’s also a delusion to suppose that the government in a liberal democracy such as the United States could become so tyrannical that armed insurrection, rather than democratic procedures, would be the best means of constraining it. This is not Syria; nor will it ever be. (Jeff McMahan, Why Gun Control Is Not Enough)
McMahan follows this with an unsupported assertion that, had the Egyptian public made use of guns, they would not have succeeded in removing Mubarak. I say this is ridiculous: revolutions need guns, and while they are no longer sufficient they are still necessary. Missiles can destroy tanks but they can't hold a frontier; drones can kill leaders but they cannot communicate to the international community that this is a popular uprising rather than a mere coup d'etat.
I'm also slightly nonplussed by the assumption that armed resistance to a government must always constitute "armed insurrection". It is surely possible to - by force - compel the government to stay within its bounds without challenging its dominance or authority. The most recent example of this would be Cliven Bundy, but a more presentable case would be that of the Black Panthers.
In any case, let's assume that the USA (and, for that matter, the UK) are in no danger of becoming so oppressive as to merit rebellion. Would this make banning guns a good idea? I'm not going to be able to answer the question in full here, but I shall present a (to my knowledge) completely original argument in favour of developed and generally civilised nations allowing their citizens to own guns.
The argument is roughly as follows: while the nations which we inhabit may not merit rebellion, there are many nations which do. (When I say that a nation "merits rebellion", this should not be taken as an endorsement of rebellion in this country; rather, I mean that the country is sufficiently badly governed that (a) a revolution might possibly be a good thing were it to happen, or that (b) the threat of rebellion is useful as it acts as a limitation upon the tyrannies of the state, since dictators will fear rebellions and wish to avoid causing them).
In these countries, it is good for guns to be possessed by the general population, as a check on state power. Therefore, we should wish to avoid these countries passing anti-gun legislation. Indeed, allowing its citizens to possess weaponry may be seen as the sign of a state which is willing to be responsive to their demands. But if the more civilised and powerful nations of the world are banning guns then this becomes harder, for two reasons. First, this weakens the strength of permitting private citizens to own guns as a signal for democratic intent; second, it weakens or removes the moral authority of nations which seek to compel gun toleration elsewhere while not accepting it in their own countries. Hence, for the sake of citizens of the developing world, gun ownership should be permitted in developed nations and positively encouraged amongst the oppressed peoples of the world.