The Championship promotion hopefuls looked set to leave London with a shock 1-0 win following Robert Snodgrass' 54th-minute penalty, but were denied by Cesc Fabregas, also from the spot, with 30 seconds of normal time remaining.
For so long the game carried a striking resemblance to Leeds' last FA Cup campaign, when they beat Manchester United and drew at Tottenham while still in League One.
Ultimately, though, the distraction of the cup almost cost United promotion and, with a replay to come against the Gunners next week, Howson is eager not to go down the same route again with his side currently putting together a strong push for a return to the Premier League.
"We have Scunthorpe to play next before the replay and that's the focus," he said. "We've got to get on with the league and take each game as it comes.
"It's nice for the fans to go to a place like the Emirates and as players, it's where we want to be, and I'm sure the fans want to visit more often."