Any article that does not precede the word "immigrant" with the word "illegal" is disingenuous propaganda.
Therefore, 1) the author of any article that attempts to substitute 'immigrant', 'migrant' or 'worker' for 'alien', or to substitute 'undocumented' or 'transient' for 'unlawful' ('illegal' is technically improper but has nice assonance), is either a complete ignoramus or is willfully attempting to deceive, and 2) any article containing such gratitous misrepresentations is kwapola to start, and not worth the reading.
Actually, they are illegal aliens. Immigration is a legal process of granting residence->citizenship to non-citizens.