How to destroy Egypt?By the Nile river,97 percent of the population of Egypt live on the Nile river so if you were to pour poisonous chemicals(e.g cyanide), you would effectively be ending Egypt.Since Egypt has no other major bodies of water, they would die from either the poisonous chemicals or dehydration.You also would be taking out some of Ethiopia and Sudan since they too use the Nile river.
If this was to happen Egyptian society would collapse and millions or even 100s of millions would die, Egypt using the the Nile river as their own source of water puts them at high risk. Since Egypt has poor ties with it’s neighbors (like Sudan) they would most probably not come their aid. Egyptians would go extinct because of a lack of water supply.