New York City has a population of over 8 million in an area around 500 sq miles. Mississippi has a population of less than 3 million in the whole state. I don't think comparing how it spread in NY to us is that valid.
First of all, this is a highly contagious novel virus that spreads very easily from human to human. Early estimates are that an infected person spreads the virus to 2.5 people. That doesn't sound too bad, but if that number stays true, exponential math says one person can be the source to spread the disease to almost 1,000,000 people in 12 weeks time. (2.5^12).
What we do know is that that rate of transmission will be different in different places. NYC has a different population density than Rochester, NY than Caledonia, MS. The rate of spread is much slower, but will still stand up over the long term relative to our hospital capacity.
Let's take a city like Columbus. Today we may have 4 infected. Let's assume because of the low density of of the city, we use a factor of 1 transmission per person on average (some will be 2, some will be 0).
Okay, so in week 4 we only have 32. That's pretty manageable. Week 8 that becomes 512 though, and if there is a 10% hospitalization rate, that's 25 NEW hospitalizations the week we hit 512. How much stress is that on Baptist? How many ventilators do they have?
Then it starts to get real. If the rate of infection continues, week 12 is about 8,000 infected and 409 NEW hospitalizations.
The next week is basically peak infection for Columbus because most people will have been sick already and herd immunity starts to apply. People will continue to get sick and need hospitalizations but it won't spread as easily because the virus has fewer chances to spread to new hosts and infect the next person down the line.
This model is napkin math and there are a lot reasons why the infection rate will slow as the disease progresses, but you can see that even with conservative estimates it goes from not a big deal to a huge deal very quickly. We can't stop it with what we have today, so all this social distancing is about buying time. It's about not letting it go from 512 to 8,000 in 4 weeks until we can get hospitals ready, develop medication to treat the symptoms, and hopefully develop short term and long term vaccines.
TLDR; It's going to spread more slowly in MS, but the more we can push it out the better chance we have of treating the people who need critical treatment when we get there.