Dear NFL, women matter ...

There's no shortage of reasons to condemn the NFL for its pitifully inadequate two-game suspension of Ray Rice, the Baltimore Ravens running back who knocked his then-fiancée unconscious in a casino elevator in February.

I could write about the hypocrisy of Roger Goodell or the troubling message it sends to American women.

But if there's one lesson we can extract from Rice's suspension, it's that such arguments don't carry much weight with the NFL.

So, instead, let's look at Rice's slight punishment through the green-stained lens Goodell looks through every single day: money.

The NFL's financial success has reached new heights during Roger Goodell's tenure. And further growth is important to the commissioner: In 2010, he told team owners he aims to triple league revenue to $25 billion by 2027. That's more than companies such as Time Warner Cable, Xerox and General Mills made last year.

Goodell's goal is lofty, but reasonable. While many sports and entertainment providers have struggled to gain market share in an increasingly crowded field, the NFL's popularity has surged. Over the past decade, average viewership of prime-time NFL games has increased by 31 percent to 20.3 million, according to Nielsen. In 2013, every network that had broadcast games reported increased viewership. Most weeks, in fact, NFL games aren't just the most-watched sporting events on television -- they're the most-watched thing on TV.

The league's success is astounding -- but it can't last forever. Dallas Mavericks owner Mark Cuban's doomsday prediction that the "hoggy" league will become oversaturated and implode within 10 years may have been overly dire, but there was a grain of truth to his prophecy. Football isn't a perpetual motion machine; it needs new external sources of energy to fuel its expansion.

As with any business, the NFL has two paths to potential growth. It can diversify its product line -- possible, but unlikely -- or it can go after new markets. Goodell's interest in putting a team in London makes it obvious that the league is pursuing the latter route.

Of course, it's always easier to grow at home. The lowest-hanging fruit, American men, may already have been plucked, but there are still large swaths of the U.S. that haven't fully embraced football -- underpenetrated segments of the market, in business-speak. The largest of those segments is female. The NFL says women make up about 45 percent of its fan base, while research firm Experian Simmons put the number at 36 percent. According to Nielsen, 35 percent of viewers of regular-season games last season were women.

That means women represent a huge growth opportunity. And the NFL knows it. It's why the league runs so many commercials targeting women and sticks pop-up boutiques inside stadiums, stocking them with pink jerseys and tank tops and something called a "Fanicure" nail polish set. Whatever you think of #nailgating, these efforts seem to be working: The NFL says sales of women's apparel have tripled over the past four years.

But marketing has its limits. People try new products for a number of reasons, ranging from quality to price. But brand loyalty, as any Apple stockholder will tell you, is driven by something deeper. Successful companies don't just sell goods and services -- they sell culture. They sell coolness (Nike) and wellness (Whole Foods) and manliness (Budweiser).

Football is no different. Women won't become fans of the NFL because of baby T's or theme nights. They'll embrace the league when they believe its values align with their own.

When the news about Rice broke Thursday, I saw scores of female football fans tweeting expressions of horror and disappointment. Several said they felt like the NFL had turned its back on them. Jets season-ticket holder Naomi Lindower tweeted that she was disgusted with the decision.

"I'll always love football, but this just makes me mad," Lindower says. The league's actions, she adds, will make it harder for her to recruit other female fans, including her own daughter. "They'll say, 'Why should I be interested in a sport that doesn't support women?'"

The NFL should ask the same question -- if not for moral reasons, then for financial ones.