Islam spread through military conquest, trade, pilgrimage, and missionaries.
Operation Rolling Thunder was a sustained bombing campaign against North Vietnam. This was a campaign run by the troops of the United States and the Republic of Vietnam forces (South Vietnam) and took place from 2nd of March 1965 until 2nd of November 1968. There were several reasons for the operation including stopping the flow of North Vietnamese commodities and men into the South, bombing North Vietnam's transportation system and to boost South Vietnam's morale.
The fastest way to communicate across continents in the 1500s was by ship. If you wanted to bring a certain message across a continent than there was no faster way than actually sending it on a ship and waiting for the ship to arrive safely to the other continent.
Answer:
World leaders agreed to limit construction of large warships
