Englishman Webb produced 14 yellow cards, including two for Dutchman Johnny Heitinga, as Spain beat the Netherlands 1-0 in extra time in a bad-tempered contest.
Webb and his English assistants, Darren Cann and Mike Mullarkey, were criticised for their handling of the Johannesburg game, but Webb said he looked back on his performance with pride.
Asked about De Jong's karate-style kick on Xabi Alonso after 25 minutes, Webb admitted he made a mistake in only booking the Manchester City player.
"We wanted to be a steady hand but equally we wanted to do our job properly, and if there was a clear red card we would do it," Webb told Reuters after a less arduous spot of officiating for local boys' teams at Manchester City's stadium on Wednesday.
"When I look back on the full two hours of that game, which of course I have, there is not much I would change.
"One of the things I would change is the colour of the card for De Jong's tackle.
"Having seen it again from my armchair several times in slow motion and from different angles, I can see that it was a red-card offence. But at the time the decision not to red-card him was not based on me not wanting to send someone off in the World Cup final, it was based on the viewing angle I had.
"What I couldn't see was the actual contact on Alonso through the back of Alonso with (Mark) van Bommel just to his right - the view was obstructed somewhat.
"I could see the foot was high and from Alonso's reaction there must have been some contact, even though I couldn't see the contact, and being 25 minutes into a World Cup final I wasn't prepared to guess. I wasn't prepared to fill in the blanks in my head to say that was possibly a red-card offence.
"I wanted to base it on what we could see, so therefore I decided to show a yellow card."
'MENTALLY DRAINED'
Webb was booed by Dutch fans at the end of the game and was criticised by Netherlands coach Bert van Marwijk. Liverpool's Dirk Kuyt, one of only two Dutch outfield players to escape a booking, said Webb had cost them the World Cup.
However, the Englishman, who also refereed last season's Champions League final, said the enormity of the match had resulted in a petulant contest that left him "physically and mentally drained".
"We went into the game wanting to be a sensible hand over a very important occasion, wanting to understand the emotions and the pressures the players were under," said Webb, who turned 39 three days after the final.
"I sensed very early on the field the players were under a lot of pressure, they were very close to winning the ultimate prize for their country for the first time."
Webb was in Manchester to meet FIFA's World Cup 2018 inspection committee, which has been touring England's bid stadiums.
He said the World Cup final had been the most demanding game of his career. "We had hoped for a smooth game, where all the focus would be on the players, the quality of the goals and the foot
