Are illegal immigrants acting immorally?

People like Governor Brewer often say that we are a nation of laws, and that is why we must make a strong stand enforcing our immigration laws. Are people who insist on a strong stand against illegal immigration gratuitously assuming that persons who enter the country illegally are acting immorally?  If the only way to support your family was to enter another country illegally, wouldn't you have a moral obligation to break the law, since you have a moral obligation to support your family which trumps your obligation to obey the law?

I'm not drawing any strong conclusions from this, necessarily. Recognition of this is compatible with strong enforcement strategies such as SB 1070. But I don't even hear this point mentioned or acknowledged by defenders of strong enforcement.