England are firm favourites to book their place in the last-16 at Al Bayt Stadium, following Monday's 6-2 thrashing of Iran. But the first week of the tournament has already seen Saudi Arabia beat Argentina and Japan stun Germany.
Turner believes the world game is “levelling out" and has told Gareth Southgate's side that anything is possible.
“You can't take any game for granted," said the 28-year-old, who helped the USA to a 1-1 draw with Wales on Monday. “You want to go out, put on your best performance.
“The world of football is levelling out. National teams have game-plans, they've been investing in youth for a number of years, they have guys playing at the top level all over the world.
"When you have one team following the same message, you can beat anyone on any given day."