Increased food production, medicine advancements, better health conditions, and increased birthrate
Advantages:
From a conservative or state-based ideology: it is much easier to control population since they rarely receive "strange" ideas or influence from outside. Domestic policies become much more important. In so, it becomes easier to set popular aims targeting citizens.
The country could(historically seen) stand the best defense against outside powers which could try to set an invasion. For example, the Great Wall of China turned out to set a strong defense against Mongols and other menaces along many centuries.
Disadvantages are listed:
Trading with other countries can influence negatively on economic growth, as there is no autonomous country even if it results as big as China.
Trade has become key in today's globalized world, henceforth the need to collaborate or cooperate in economic exchanges is a necessity to keep up the pace in global affairs.
He worked on the telescope by improveing it and he studied astronomy
President John F. Kennedy. Upon taking office, Johnson, also known as LBJ, launched an ambitious slate of progressive reforms aimed at creating a “Great Society” for all Americans. Many of the programs he championed—Medicare, Head Start, the Voting Rights Act and the Civil Rights Act—had a profound and lasting impact in health, education and civil rights. Despite his impressive achievements, however, Johnson’s legacy was marred by his failure to lead the nation out of the quagmire of the Vietnam War. He declined to run for a second term in office, and retired to his Texas ranch in January 1969.
