In the article "The Obligation to Resist", an excerpt from "Silent Spring", Carson focuses on her main concerns for the environment. For millennia, Mother Nature has been the only modifier capable of shaping the environment. In turn, this caused species to adapt for survival. However, with the birth of man, the delicate balance shifted. Humans now possess the ability to alter the composition of their environment. This is a power that should not be taken lightly or abused. However, humans are often blind to corruption until it is too late, and so the inevitable has happened. The man abused his power and did not see the consequences. This is a general concern of Carson's: "The most alarming of all man's attacks on the environment is the contamination of the air, land, rivers and sea with dangerous and even lethal materials (Carson)." Chemicals dumped into rivers pumped pollution into the air. The toxic radiation released from nuclear explosions in the form of Strontium 90. The endless pesticides sprayed on crops and trees. All these are the weapons used in "man's war against nature".