Guns don't even make the top ten, though they do play a large part in #10.
Heart disease: 611,105
Cancer: 584,881
Chronic lower respiratory diseases: 149,205
Accidents (unintentional injuries): 130,557
Stroke (cerebrovascular diseases): 128,978
Alzheimer's disease: 84,767
Diabetes: 75,578
Influenza and Pneumonia: 56,979
Nephritis, nephrotic syndrome, and nephrosis: 47,112
Intentional self-harm (suicide): 41,149
I believe guns are a small part of #4 Accidents, in addition to #10.
#1, #4, #6, and possibly #5 are mainly caused by poor diet, stress, lack of exercise
#2, #3 are heavily related to smoking, air pollution, industrial jobs, and then a myriad of tiny factors, and mostly lead to death among the elderly
#8 mainly kills people with compromised immune systems, again mostly elderly
#9 is related to a pretty wide variety of underlying issues (various viral infections, cancer, diabetes, certain drugs, ...)
In any case, most of these things are either completely random and unavoidable “acts of god” which we have no way to work on as a society beyond improvements to medical treatment and continuing research, or else are personally avoidable via good lifestyle choices (sleep, diet, exercise, etc.). Gun and car deaths, however, are both largely avoidable at a societal level, and are inflicted on innocent people who have limited choice in eliminating the risk. To be safe, it’s possible to move to areas with walkable neighborhoods, good transit, and no rednecks packing heat, but that’s still no guarantee that a drunk driver won’t hit you or a cop won’t randomly shoot you in the back (though this is more of a problem for non-whites).
* * *
If we really wanted to organize our society around reducing all-cause death rates, the #1 priority would be to reduce poverty, unemployment, and income inequality. The ideal approach would be to tax the **** out of inheritances, wealth of all kinds (especially property), and have very high marginal income tax rates at the top end (e.g. anything past $1M income could be taxed at 80%), with capital gains treated as income. This money could then be distributed widely as an unconditional basic income to all citizens (or even all residents). This is not politically feasible in the post-Reagan greed-is-god era, but would have a great effect on many causes of death including in particular heart disease, strokes, respiratory diseases, accidents, diabetes, and self harm, and would also greatly reduce crime and violence in general. Other policy goals in this general area include de-financialization of the economy, increased infrastructure spending, reform of the criminal justice system, and dramatic education policy reform, in particular spreading a lot more money to schools in poor neighborhoods.
Priority #2 would be to get everyone into a single-payer healthcare system. The current US healthcare system is the most inefficient in the world, combining incredibly high prices with awful outcomes. We could pick pretty much any other developed country in the world as a model for something better. There are lots of choices in the details.
Priority #3 would be to change cost/incentives related to poor diets, by dramatically changing agriculture policy to reduce subsidies for corn, wheat, and soybeans, institute high taxes on sweeteners of all kinds, make heavily processed foods and restaurant fast food more expensive, and improve access to fresh vegetables nationwide. I’m sure there are industrial-scale ways of efficiently getting basic nutrients to people if we put our brightest minds on the task.
After that, the changes are going to be much harder. Changing nationwide zoning laws to restructure all of our urban areas into more walkable mixed-use neighborhoods with better access to jobs, stores, and public transit is a nearly impossible challenge at this point. Unfortunately, whether we do anything grand as a nation or not, many suburbs are going to become bankrupt ghost towns in the coming decades, with infrastructure maintenance costs outstripping available tax revenue.
Changing work culture so that professionals don’t spend 10 years in awful hazing rituals like medical residencies and junior positions in law firms, and stick to <40 hours/workweek or less is going to be pretty difficult. For whatever reason, Americans love to work and firms love to force more work hours, even when it can be clearly demonstrated that working more hours leads to quickly diminishing returns and at some point negative returns. Providing better childcare benefits, proper enforcement of sick days, sufficient vacation, etc. is going to be a political non-starter in a country where labor is now entirely defanged.
Etc.
