Tom Cruise has been welcomed back to the nation’s multiplexes, with “Mission: Impossible — Rogue Nation” heading for a U.S. opening weekend that could top $50 million, according to early estimates Friday.That could be four times as much as that for the rebooted “Vacation,” which is underperforming with a projected Friday-Sunday total of $12.5 million and a disappointing five-day cume ar0und $19 million.“Mission: Impossible — Rogue Nation” is dominating Friday business, with a first-day total of at least $20 million at 3,956 locations. That figure includes $4 million from Thursday-night preview showings.Paramount’s fifth entry in the “Mission: Impossible” franchise has launched amid a marketing campaign with Cruise — one of the best promoters in the business — hitting the circuit to discuss the film and its eye-popping stunts, such as his clinging to the side of an Airbus A400 plane during takeoff.The studio has been cautious in its guidance for the action-adventure, which carries a hefty $150 million budget, asserting that its tracking shows “Rogue Nation” on pace to open to $40 million over the weekend. Some analysts believe that number could top $50 million, given the strong critical support, with a 93% rating on Rotten Tomatoes.