The Spain midfielder scored a stunning left-footed strike after earlier efforts from Olivier Giroud - his first Premier League goal since his summer move from Montpellier - and substitute Walcott had overhauled Mohamed Diame's opener for the Hammers.
Walcott told ESPN: "He's come in to the Premier League and taken it by storm - he's our conductor.
"His goal was fantastic - I don't even know what-footed he is, to be honest."
Wenger, his delighted manager, added: "It was an outstanding performance. If you love football, just watch him play - it's a delight to watch him."
West Ham snatched the lead against the run of play in the 21st minute.
The ball was worked down the left channel and Diame cut inside Aaron Ramsey to fire an angled drive into the top corner.
Arsenal had a chance to equalise when Giroud just failed to connect with Per Mertesacker's flicked header through the six-yard box.
The French striker, though, did bag his Premier League goal four minutes before half time.
After winning the ball in midfield, Giroud stabbed it out to Lukas Podolski on the left. The German darted to the byline before cutting the ball back across goal where Giroud arrived at pace to slot home.
Giroud was relieved to finally get open his Arsenal account.
"I'm so happy to score my first goal and assist my friends in the team," the France striker told ESPN. "Everyone was talking about this goal, saying 'don't worry, we trust you, keep going, concentrate'. I stayed confident."
The France striker turned provider for Walcott on 76 minutes as the England winger timed his run to perfection to beat the offside trap and neatly finish past Jussi Jaaskelainen.
Wenger said: "Theo has that in him. One or two years ago when he got in front of the keeper, he did not always finish the chance."
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