Definitely plastic

PETA's website

Is the answer me

The soy industry liberal agenda PC culture "third wave feminists" safespaces veganism nonwhite santa invented ME

Rural electrification

Curved screens.

smartphone

Non-biodegradable plastic? (Also one of the best, in some sense, but in the long run one of the worst.)

Vivisektion

Human beings

Unmanned combat drones, removing the human risk to one's soldiers makes certain cowards a lot more cavalier about blowing up certain other humans

Also home 3D with glasses, they need to quit trying to make that happen, but they are going to try again in about 5 years

Speech. It transfers ideas from one mind to another and there is almost no defence.