in a gunfight with police. the united states also naturalized more than 750,000 citizens last year, new citizens including dzhokhar tsarnaev. he's the 19-year-old younger brother, now charged with using a weapon of mass destruction. he is an american. both brothers in the united states legally, both brothers accused of perpetrating terrorism against a country that embraced them, and all of this as the senate begins consideration of a bipartisan bill to reform the u.s. immigration system. it would allocate $3 billion for tighter border security, provide a path to citizenship for about 11 million people in the country illegally, undocumented immigrants, and create new guest worker programs. some conservatives say what happened in boston should delay this effort until we learn more about how the system failed. liberals say opponents of immigration reform are exploiting the bombing. >> let no one be so cruel as to try to use a heinous acts of these two young men last week to