15. Speedy Clean Service, Inc. provides janitorial services for office buildings; a number of its employees are Hispanics who have entered the United States illegally. When several employees try to organize a union to represent them, Speedy Clean fires all of its workers. The discharged employees file unfair labor practice charges with the NLRB; the employer argues that the illegal aliens are not entitled to protection under the act. Are illegal aliens included within the definition of "employee" under Section 2(3)? Explain your answer. [See Hoffman Plastic Compounds, Inc. v. NLRB, 535 U.S. 137 (2002).]