MILWAUKEE—Frequently choking back tears, African-American computer technician Michael Shaw bid an emotional goodbye to his wife and 6-year-old son before making his morning commute Thursday, sources confirmed. “I don’t know when or if I’ll see you guys next, so I just want you to know how much I love you,” Shaw said, his voice breaking as he prepared to embark on the 25-minute trip, including a stop at a Dunkin’ Donuts drive-thru, from which he might not return.