Henry felt England's failure to kick for goal in the dying minutes of the match and draw level with Wales on the scoreboard was symptomatic of their "poor decisions".
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"They should have kicked that goal with three minutes to go. Goodness me. Owen Farrell doesn't miss. He's a class goalkicker and they blew the opportunity and let Wales into the game," said Henry who watched the game on television in Italy en route to the World Cup.
Henry said the decision reflected the mental quagmire the host nation had got itself into ahead of the Cup.
"The whole weekend has been that sort of England," he said. "They're not sure what they're doing, they're not sure about their selection, they're not sure about how they are going to play. They just blew it, quite frankly. They made poor decisions, let my mates back into the game and they did the business."
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Henry felt Wales' biggest challenge from here would be overcoming their horror injury list.
"They're decimated. They're going to have a huge game against Fiji in a few days time. Fiji have been very impressive and I think that's a big worry for Wales going forward."
He also refused to write off England.
"It's just a matter of who's going to get through that pool and there's some big games to come.....it's still wide open, England can still qualify and they can learn from this situation."