I remember years ago when I was back in high school when there was this sci-fi-thriller called "Firestarter" starring David Keith and a very young Drew Barrymore, still fresh from her debut in "E.T." in 1982. It was all about a girl and her father trying to flee from a sinister government agency because of her terrifying abilities at pyrokinesis.
Well, there was this other Japanese movie that I believe my parents had been watching on our ancient Panasonic VHS player that had a somewhat similar plot. Titled "Yasei no Shomei"（野性の証明...Never Give Up）, it came out in 1978 and starred the stoic Ken Takakura（高倉健）who would find Hollywood fame in "Black Rain" several years later and a very young Hiroko Yakushimaru（薬師丸ひろ子）who wouldn't end up in the recording booth for another few years. I remember seeing that one scene near the end of the movie where a whole bunch of SDF tanks were ominously approaching the characters for one last battle.
On hearing the theme song, memory engrams started flashing on and off in my brain. I know that I have heard the song before whether it be from the movie itself or on some TV retrospective of kayo kyoku. Whatever the case, "Senshi no Kyuusoku" (Respite for the Warrior) by singer Yoshito Machida（町田義人）is a nice slice of mellow 1970s pop.
Up to now, I've been partial to instruments such as the Fender Rhodes piano and a good thumpy bass. Now I realize that I have to add an especially twangy guitar. And "Senshi no Kyuusoku" has it in good amounts. It might be because that guitar automatically triggers the release of some relaxing endorphins of nostalgia, and there is something of the "lone rider traveling the open road" feeling to it. Basically the whole song has that emotion hanging off of it.
Written by Keisuke Yamakawa（山川啓介）and composed by Yuji Ohno（大野雄二）, "Senshi no Kyuusoku" was a big hit for Machida who had started out in the Group Sounds bands a decade back with Castle & Gates（キャッスル&ゲイツ）and then Zoo Nee Voo（ズー・ニー・ヴー）. The single which was released in July 1978 managed to sell perhaps up to 850,000 records as it peaked at No. 6 on Oricon.
After Machida left Zoo Nee Voo in 1970, he took on a solo career and in the next 7 to 8 years, he created about 400-500 commercial jingles for TV. There is something about "Senshi no Kyuusoku" which would make it ideal as an ad song for some product...perhaps whiskey. Very comfortable.