This song is basically a love song from Bono to Ali, to sum it up.
katie duncan nick_tiger_babyyahoo.com (contributed before the 20:th of February 1998)
This song refers to a baby when it is in its mother's womb. The mother's and the baby's hearts are both beating in one body - as one. This fits in with the "theme" of Bono's great love for his mother.
Janice Browning jbrowninarches.uga.edu(22:nd of April 1999)
Consistent with the album War's theme, this song was Bono's internal struggle with the political issue of Northern Ireland and whether it should be united with the Republic of Ireland --"two hearts beat as one." He admits, "I don't know, I don't which side I am on. . ., I don't know my right from left political "right" and "left") or my right from wrong" (what is the best way to accomplish a united Ireland). Many support a united Ireland, but not at the expense of violence. During that time, Bono described U2 as crusaders against violence. See for example the "Two Heart Claddaugh ring" that has no crown (no English rule), but two hearts -- symbolizing a united Ireland. Two hearts, beating as one.
SJOrgan sjorganearthlink.net (24th of April 2010)