It's conventional wisdom, written in stone and set in concrete, that Republicans are stronger on terrorism while Democrats do better on other issues, particularly domestic ones. On Monday, we covered the latest ABC/WaPo poll, and included this graphic:

Greg Sargent at the Plum Line reviewed the same poll, and noted that terrorism number:
Obama Leads Republicans By Over 20 Points — On Terrorism!
Does anyone else find this number from the internals of the new Washington Post/ABC News poll just stunning?
Who do you trust to do a better job handling the threat of terrorism — (Obama) or the (Republicans in Congress)?
Obama 55%
Republicans in Congress 34%
A year ago, when the conventional wisdom held during the campaign that terrorism was a weak point for Obama, would you have predicted that he would come to hold a 21-point lead over the GOP on the issue?
To highlight that point, we reviewed older polling data at Polling Report on terrorism, and found some interesting comparisons of Dems and Republicans. Three polls (Fox, CNN/USA Today/Gallup and NBC/WSJ) went back before 2006. In that 2006 year, Republicans had a generic 8-10 point lead on terrorism inmultiple polls. But going back further, in 2002 Republicans had as much as a 36 point lead.
Who would do better on terrorism, R's or D's? (For exact wording, click on name of poll)
Republicans Democrats Difference (D - R)
CNN/USA Today/Gallup 2002 57 22 -35
NBC/WSJ (RV) 2002 49 13 -36
Fox 2003 53 19 -34
ABC/WaPo (Obama v GOP) 2009 34 55 +21
Seems obvious to me the reason Republicans lost their edge is Iraq. The day Bush claimed that we invaded Iraq because they had WMDs, and tried to link Al Queda and Saddam, was the day the Republican advantage on terrorism began to disappear.
Regardless of whether you agree about why, that's quite a shift in the numbers... more than 50 points in seven years. Make a note of it. You may need it one day to correct some conventional wisdom.
Added: yes, the question of a sitting president v another party is different than generic R v D, and previous data exists on the economy for the last three presidents v congress, but not for terrorism (at least in the ABC/WaPo poll). The point remains, however, that assuming the GOP always has an edge on terrorism no matter what is out the window.