A little bit of background (hope it helps you):
It's late 70's and Bowie had just moved to Berlin to clean himself up from the drug and alcohol fueled pace he had been running previously in Los Angeles. "Heroes", the album, comes smack in middle of the what is considered as the Berlin trilogy ("Low" & "Lodger" being the bookends of this set) made with the very excellent producer and synthesizer whiz Brian Eno.
Bowie sought creative inspiration at that time from the city itself, including the Berlin Wall and its history. In fact, the wall was in viewing distance from the very studio he chose to record in (trivia: the studio used to be a Gestapo ballroom). He conceived the song about two lovers living on opposite sides of the wall and willing to risk it all to meet and ultimately die there in a hail of bullets from one of the gun turrets. It captures that desperate moment when one will die for love and emphasizes the ability to rise above all obstacles. (I picture the man mortally wounded but still trying to reach her by crawling in the dust of no man's land. And her in her wedding dress torn and snagged on the barbed wire reaching out to him in her last moments.) It can be viewed as over the top on one hand, but I feel Bowie's humanity at it's strongest in this moment. It's pop perfection.
Good morning America, how are you... Don't you know me, I'm your native son