Top strategist Kenneth Fisher says he’s not giving up on foreign stocks, despite the fact that they’ve lagged during the bull market.

 “Increasingly I hear investors ask if they shouldn’t just junk overseas stocks and stay home,” Fisher writes in his Forbes column. “Unless you’re some kind of supertimer savant (in which case, you’re certainly not reading me), that’s a big mistake. U.S. and foreign have largely traded leadership in fairly long and tricky-to-time rotations. … In the very long term the overall difference between both, correctly calculated, is essentially a rounding error.”

Fisher says the back-and-forth isn’t due to economic strength. “Ultimately supply catches up with any demand shifts and often overshoots. Supply shifts control long-term pricing,” he explains. “If some stock categories get too hot-and-pricey, mass supply is created via stock offerings to tap that cheap money–and when overdone drives it all down. If stocks get too cold, and cheap, supply is eventually destroyed by endless buybacks and cash-based takeovers–capturing those cheap earnings (relative to interest rates). That shoves those stocks skyward, until they rival faster-growing, pricier categories, wherever in the world.”

But Fisher says that while a foreign bounce-back may be on the horizon, you shouldn’t go all-in on foreign stocks because the timing is so tricky. Instead, stay globally diversified, he says, because it’s a smoother way to get to the same long-term return.

Currently, several foreign firms whose shares are trading on US exchanges are getting strong or some interest from Validea’s Ken Fisher-based model. Among them: Magna International (MGA) and Telecom Argentina (TEO).