Coasts can be the life line of a country. It affects many things of a country.
The temperature of the coastal region remain more or less the same and balanced in all seasons. We don't feel more cold or hot due to the coasts. It rains properly and hence the agricultural activities can be done. Also some people earn money by selling fishes and other things which they get from the ocean. Some times there are natural gas reservoir or petroleum reservoir beneath the sea. It helps the country to be self-reliant as far as fuel is concerned. They need buy fuels from other countries. We can have ports if we have coasts and the shipping of goods to other countries will be easy and economical. This will also help in connecting the different regions of the country and also in connecting different countries. These things will help the economy of the country to flourish.