It's certainly a valid question.
While the Falcons do have just a hair more than $30 million in cap space this offseason, they also have a whopping 17 impending free agents. There are also a few big names that could potentially seek a larger deal elsewhere and test the market.
The two big ones are cornerback Brent Grimes and middle linebacker Curtis Lofton. Those two far and away possess the most open-market appeal: both are in the prime of their careers, both are Pro Bowl-caliber starters (many around the league feel Lofton was snubbed the past two seasons) and both will want some security for the future.
Grimes and Lofton are both integral starters on the defensive side of the ball; we all know that. But the thought remains: will the Falcons actually use the franchise tag on either player? Well, there's a long answer and a short answer.
The short answer would be no.
The long answer goes something along the lines of, "Why pay $10 million for a player who doesn't even want to be there?"
Historically, Thomas Dimitroff has been reluctant to use the franchise tag on anyone. Despite his tendencies to stray from The Patriot Way from time to time, the tag hasn't exactly been a favorite of either Dimitroff or his hooded mentor.
In regards to Grimes, it's not hard to imagine the coaching staff still being irked by his sitting out the Giants game, even though he's arguably the best Falcons cornerback since Deion Sanders and likely to cash in on a big-time deal somewhere. It may have left a bitter taste in the mouth of Mike Smith, and I'm not so sure he really wants Grimes back after that disappointment. But I'm not Mike Smith.
As for Lofton, I'm not sure how Mike Nolan feels about him. There have already been rumors that Lofton may become a two-down player in Nolan's system -- with Sean Weatherspoon moving inside on third down -- and that may not appeal to 5-0.
Finally, $10 million is a pretty hefty sum to tie up in any one player, and unless he's superstar caliber (I'm talking Patrick Willis, Nnamdi Asomugha, etc.) I'm generally against its use. The Falcons have a laundry list of needs to address this offseason, and while cornerback is close to the top, I'd give the offensive and defensive lines higher priority.
So no tags from the Birds. The defense could look really different by training camp.