Gary Fuchikami only regards military service as a legitimate obligation of immigrants who are undocumented. He should remember that they also serve because they take jobs that Americans do not want and they pay their taxes and get nothing in return. They obey our laws and keep out of trouble. 

Many US citizens do not do these things. Should we revoke their citizenship for that? 

I think what he is asking is that will undocumented immigrants defend our country if called upon to do so. Why not? Mostly all consider the US to be their home. Wouldn't they want to defend their home?