People in the United States on tourist visas are not prohibited from bearing arms (in fact gun ranges are major tourist destinations in some parts of the country). Purchasing arms is subject to a higher legal standard, but is also not wholesale prohibited, just subject to a few extra rules. For example, a tourist who acquires a hunting license in any state can purchase a firearm.
...and in any case, this is not a citizen/non-citizen issue, as GP claims - lawful permanent residents have the same 2nd amendment rights as citizens.
Well yes, but that is a privilege that the country bestows upon you as a token of good will and faith - not a natural right under the constituion; and I would not expect it either. Should I be allowed the affordances of the 1st amendment while on American soil to advocate for the fall of the American republic? I would be deported very swiftly.
In the time the constitution was framed, "well regulated" meant properly trained and not "subject to 30 million pages of government control and criminilization".
If you want to cherry pick certain parts of the second amendment - I can do that too: "the right of the people to keep and bear arms shall not be infringed".
Please stick with weapons available at time constitution was written of not very reliable ~3 shots per minute fire rate. Gunpowder cannons are also OK.
Law evolves along with technical progress and 2nd amendment is not exception.
When you write your reply on parchment with elderberry ink, seal it with wax, and have it delivered by pony express we can have a discussion on the limitations you are proposing on the first amendment with your long debunked argument.
Also there were repeating rifles, cartridge based rifles, and citizens owned artillery pieces and war ships in the era in which the Constitution was written.
You should read Heller - Justice Scalia wrote a great deal about your argument and why it is absurd.
The framers wanted the people to have access to the same weapons the government did - to allow the people to have a very real check over the overreach of said government.
Benjamin Franklin was an inventor - if you think when they wrote the second amendment they didn't think "gee, maybe guns will shoot faster someday" then I don't know what to tell you.
...and in any case, this is not a citizen/non-citizen issue, as GP claims - lawful permanent residents have the same 2nd amendment rights as citizens.