England's record run-scorer in all formats, Pietersen was sacked after a 5-0 whitewash in the 2013-14 Ashes series and was told in May by former captain Strauss that he would not be considered for an international recall.
The team has simply "moved on", said Strauss, who had a frosty relationship with the fellow South Africa-born Pietersen.
"The danger at that time was that particular issue would overshadow everything that happened on the pitch over the course of the summer," Strauss said.
"What I was trying to do was provide clarity going forward so everyone knew where they stood.
"I think the team has moved on and the team is in a pretty good place. Some of those young guys have established themselves and that's what we will be focusing on taking England forward," he added.
England won the Ashes 3-2 but trail 2-0 in the five-match One-Day International series going into Tuesday's third match at Old Trafford.
Image: Kevin Pietersen.
Photograph: Ross Kinnaird/Getty Images
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