A sourdough starter is like a country's history because they both require a lot of attention to detail. When Thomas Jefferson and they other founding fathers wrote the Declaration of Independence they had to pay a lot of attention to detail. Being one of the most important documents in U.S. history it had to be right which is exactly why it's detail were so important. The sourdough starter requires attention to detail when storing and kneading because if the starter is too warm or too cold the yeast will die and if it is not kneaded properly it will not have enough gluten in it.
Another way a sourdough starter is comparable to a country's history is the fact that they both get better with age. When a country is young it is naive and it takes time for it to mature and become better all around. Just like a country, a sourdough starter takes time for it to be at its peak.
Just over 230 years ago when the U.S. was born it didn't have much to brag about. With very few cities and even less rules it was hardly able to survive but then as time went on it became a lot better just as the stretchy, elastic sourdough starter.
A final way a sourdough starter is alike a country's history is the fact that they are all about balance. When the author was making the dough for the first time she did not know the correct balance of flour when kneading to get the correct amount of gluten. Just as a country needs to have a balance of people, jobs, and natural resources a sourdough starter needs to have a correct balance of ingredients.