Ripples of anxiety are likely to be coursing through internet retailers this month. That's because two events - the introduction of the Marketplace Fairness Act in the U.S. Senate and an opinion written by Supreme Court Justice Anthony Kennedy - made it more likely than it has been in 50 years that they will have to collect taxes in states where they don't have a physical presence. If that happens, out-of-state retailers would be compelled to collect sales and use taxes in almost 10,000 state tax jurisdictions that, according to the Tax Foundation, exist across the United States.

Analyst Insight: Omnichannel commerce is the new "normal" for retail. And it's a tall order for most companies to achieve. You'll need an omnichannel road map that incorporates where you've come from and where you need to be based on your customers' expectations and your business strategy. – Joe Dunlap, Senior Director, Supply Chain Strategy, Fortna Inc.

Long a laggard in online sales, the Swedish retailer Ikea, which is privately held, has finally recognized the need for a more robust e-commerce presence.

"It's dying," says an electronics-store retailer, shaking his head as he looks out at abandoned stores and torn promotional posters in what was once the busiest market in the Zhongguancun district, known as China's silicon valley. "There are more sales staff than customers around here. Everyone buys online now."

There's a wake-up call for American digital marketers who aren't actively developing their international online markets. While there are many risks to taking your business online to other nations, the risk of not going global, or of waiting too long to make the move, almost certainly will be greater.