Oil prices may be “artificially Very High,” as Donald Trump alleged last week, but that hasn’t boosted an industry that should be a key beneficiary. On Monday morning Halliburton HAL 0.17% rounded out first-quarter earnings season for the world’s three largest oil-field-services companies. Like its brethren, Schlumberger and Baker Hughes, a General Electric company, it struck an upbeat tone. With international benchmark oil prices hovering near $75 a barrel, near their highest level since 2014, it would be hard to imagine otherwise. Yet all three have lagged behind the S&P 500 over the past year. That isn’t because investors are skeptical about the oil rally’s sustainability. Instead it is because of the huge boom in shale drilling in the U.S. and not much excitement in any of the other places where these global companies operate. Halliburton, for example, saw a jump of 58% in North American revenue and just […]