The 21-year-old England forward was a controversial omission from Fabio Capello's ill-fated World Cup squad, only to be welcomed back into the national-team fold following the dismal display in South Africa.
It may just have proved to be a decision which brings the best out of Walcott this season as the former Southampton trainee tore the Seasiders apart from kick-off at the Emirates Stadium on Saturday, sweeping the Gunners into an 11th-minute lead.
Andrey Arshavin made it 2-0 from the penalty spot after defender Ian Evatt had been sent off for a foul on Marouane Chamakh, which looked just outside the box.
Walcott added a third before the break, with Abou Diaby slotting home number four at the start of the second half and the England man - whose only international goals came with a famous hat-trick in Croatia during September 2008 - then securing the match ball with another well-taken finish.
World Cup winner Cesc Fabregas and runner-up Robin van Persie came off the bench for the last half-hour as the Gunners, who snatched a late 1-1 draw at Liverpool last weekend, moved to the top of the table, if only for a few hours, with Chamakh heading in a sixth goal in the 83rd minute.
Almost 3,000 Blackpool fans - packed into the newly renamed Clock End - had made the long journey south, perhaps more in hope than genuine expectation of another shock result.
However, Gunners boss Arsene Wenger had warned against underestimating the threat of the Premier League new boys, and Ian Holloway's men certainly started with no fear.
Blackpool broke quickly and David Vaughan tried his luck from 20 yards but shot straight at Manuel Almunia.
However, Arsenal were soon in front.
Arshavin fed Chamakh down the left, and the free transfer signing from Bordeaux quickly laid the ball off to Tomas Rosicky, who in turn rolled a pass onto the advancing Russian.
With the Blackpool defence stretched, Arshavin put Walcott clear into the right side of the penalty area, and he dispatched a first-time strike into the bottom corner in the 12th minute.
It was a vintage Arsenal goal but the hosts were almost caught cold immediately afterwards.
Stephen Crainey sent over a lovely cross from the left, which dropped to Gary Taylor-Fletcher at the far post but his downward header was just wide.
Walcott scampered away again down the right, before cleverly delaying his centre into the path of Arshavin, who crashed a half-volley goalwards, but Seasiders goalkeeper Matthew Gilks made a fine reaction save.
Chamakh almost rolled an 18-yard shot into the far corner after some more good work from Walcott on the edge of the area.
Arsenal were awarded a penalty in the 32nd minute when Evatt slid in from behind on Chamakh, in a challenge which looked just outside the box.
Referee Mike Jones pointed to the spot and despite the Blackpool protests, went straight to his pocket for the red card. Arshavin stepped up to drive the ball into the bottom right corner.
It was now a case of damage limitation for Blackpool, who brought on new signing Dekel Keinan, the Israel defender, for striker Ludovic Sylvestre.
A brilliant block from Gilks prevented Chamakh from making it 3-0, before, in the 38th minute, Walcott turned Keinan on the penalty spot and drilled the ball into the far corner.
Busy Blackpool goalkeeper Gilks saved Chamakh's near-post effort from Gael Clichy's left-wing cross. However, he was picking the ball out of the net again four minutes after the restart when Diaby swept in Bacary Sagna's centre.
Walcott completed his hat-trick in the 58th minute when he curled the ball inside the far post after being fed by Diaby.
Arshavin squared for Chamakh in the six-yard box, but the ball took a bounce just ahead of reaching the Moroccan striker, who shinned it over.
As the hour mark passed, Arsenal introduced Fabregas and Van Persie, replacing Diaby and Arshavin, to a standing ovation before Walcott was also given a well-deserved rest.
Chamakh got a home Premier League debut goal when he headed in Van Persie's corner seven minutes from time.