It's not only 'right', it's actually biologically necessary. There is at least one essential amino acid (essential meaning 'you can't get it from any source besides your food') that doesn't exist
at all in the plant kingdom: taurine.
Caveat: human bodies 'learn' to make taurine sometime during the late single-digit years. For pre-teens and above, it's not essential anymore. But unless you intend to breastfeed until you're 8 or 9 years old, you must eat meat (not eggs, and milk only if you drink enough of it that it is your primary source of nutrients).
QED: Humans, for at least a half-decade between the end of breastfeeding and the commencement of their body's ability to construct it's own taurine (which, BTW, it does very inefficiently: it's better to continue eating meat), require meat to survive. Therefore, it is not wrong to eat meat.
On a more philosophical level, everything we do as living creatures has an impact on the environment around us. As humans, we have the ability to critique that impact and ask if it's too extensive to be 'just'. When we find that it is, we choose to reduce it -- but there are easy ways to more dramatically reduce that impact than by choosing to go vegetarian or vegan. Someone interesting in minimizing their impact on the world would do much better to join a system like Polyface Farms (
http://www.polyfacefarms.com/), which feeds the soil, raises happy animals, and provides quality, nutrient-dense organic food to humans, minimizing the amount they have to consume in order to get all of their daily nutrients. Philosophically, there is no superior system that I've witnessed than Polyface.