Need help proofreading and editing this body paragraph

this is the last body paragraph for my essay, we are supposed to write about solutions other than building empires.

The Ultra-nationalism of building an empire is not the right way to preserve and expand a nation’s culture or to provide a secure source of natural resources. A way in which a nation can acquire a secure source of natural resources is through trade. One country can trade a specific good other country needs, with a good that they need. This trading practice will benefit you far greater than having a war to acquire resources; it will allow a nation to establish a trade network which will provide you with most or all of the natural resources you require. A nation cultures and religion can be preserved and even expanded by introducing new populations into your nation. If one country permits immigrants to come to their country they can teach these immigrants their culture and religion which will then promote some of them to practice this culture and even convert to the nation’s religion. This concludes that there are more peaceful methods to achieve a nation’s goal than to build empires.

3 answers

Get rid of all instances of "you" and any of its forms.
http://www.albany.edu/eas/104/topten.htm
See #7.

Clarify all instances of "they" and any of its forms.
http://grammar.ccc.commnet.edu/grammar/pronouns.htm

Clarify all instances of "it."
http://www.google.com/search?q=vague+pronoun+reference&ie=utf-8&oe=utf-8&aq=t&client=firefox-a&rlz=1R1GGGL_en___US357

Make sure all singular antecedents have singular pronouns or other referents.
http://grammar.ccc.commnet.edu/grammar/pronouns.htm
it is an argumentative essay
Writeacher's corrections have nothing to do with whether the essay is argumentative or not. She is correcting the grammar and proper essay form.