Snow: Flow of illegals not an 'invasion' Spokesman says Article 4 of Constitution doesn't apply to border issue Saying Mexico is "not the enemy," presidential press secretary Tony Snow today rejected the characterization of the constant flow of illegal aliens over the U.S. border as an "invasion." At today's White House press briefing, WND asked the spokesman: "Article 4, Section 4 of the Constitution says, 'The United States shall guarantee to every state in the Union a republican form of government and shall protect each of them from foreign invasion.' My question is, does the president believe this foreign invasion...