Historically, up until the middle ages, human populations were mostly limited by

If you think of life in the not-so-good old days, what images come to mind?  Disease, famine and war.  (That's the sort of answer you're looking for.)  The Bible book of Revelation described much of human history as a rider on a sickly, pale greenish horse given power to kill on earth by the sword, famine and plague.

Only when better methods of food production helped reduce famine, and scientific advances in medicine helped reduce disease did population progress take off.  War, well, we're still dealing with that -- though with less deaths today in the world than there were in those older eras.  (The last huge death tolls in our time came during the World Wars.)

In my honest opinion , i’d say franklin d roosevelt was a president that impacted our nation , i say this because fdr is voted among top three best us presidents and he was the longest serving president by 3 terms , usually presidents only supposed to have two terms increments of 4 years , equivalent to 8 years total before election time. and he established the fdic , through the 1933 banking act and he established the us , social security system , during his presidency, and established a national minimum wage , through the fair labor standards act , fdr led the allied coalition to victory in wwii and he played a major role in the creation of the united nations.