You do not have to be USC to buy and own a gun. And yes if a burglar come to my home and my or my family lives are threatened I will kill the bugger!
The federal law allows even a non-immigrant to purchase a gun (riffle or shotgun only) withs some exceptions.
http://www.atf.gov/firearms/faq/nonimmigrant-aliens.html#nonimmigrant-possession
Nonimmigrant aliens generally are prohibited from possessing or receiving (purchasing) firearms and ammunition in the United States.
There are exceptions to this general prohibition. The exceptions are as follows:
nonimmigrant aliens who
possess a valid (unexpired) hunting license or permit lawfully issued by a State in the United States;
nonimmigrant aliens entering the United States to participate in a competitive target shooting event or to display firearms at a sports or hunting trade show sponsored by a national, State, or local firearms trade organization devoted to the collection, competitive use or other sporting use of firearms;
certain diplomats, if the firearms are for official duties;
officials of foreign governments, if the firearms are for official duties, or distinguished foreign visitors so designated by the U.S. State Department;
foreign law enforcement officers of friendly foreign governments entering the United States on official law enforcement business; and
persons who have received a waiver from the prohibition from the U.S. Attorney General.
Significantly, even if a nonimmigrant alien falls within one of these exceptions, the nonimmigrant alien cannot purchase a firearm from a Federal firearms licensee (FFL) unless he or she (1) has an alien number or admission number from the Department of Homeland Security (formerly the Immigration and Naturalization Service) and (2) can provide the FFL with documentation showing that he or she has resided in a State within the United States for 90 consecutive days immediately prior to the firearms transaction.
[18 U.S.C. 922(g)(5)(b) and 922(y), 27 CFR 478.124, ATF Rul. 2004-1]
An Asylee is
not a non-immigrant thus the federal law permits the purchasing and owning of a gun. However, one should check the laws at state level as well as the state laws concerning CCW (carrying a concealed weapon) permits!
http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=browse_usc&docid=Cite:+18USC922
http://www.vrolyk.org/guns/alien-laws.html
Here at the forum there are quite few people owning guns, maybe someone will shed some more light on the subject. There are also old posts regarding the question.