Why is Obama so reluctant to bomb ISIL?

For some reason it seems like getting President Obama to go after ISIL is like pulling teeth.  He just bombed them for once, finally, but why isn't this a daily occurrence?  I realize that Obama is loathe to put boots on the ground anywhere, especially where he just pulled them out of, but there are plenty of things that can be done to ISIL that don't require boots on the ground.

Seeing all those Yazidis trapped in the mountains is heartbreaking, and I'm thankful that something is finally being done to help them.  I just wonder what the hell took so long and why we aren't doing more.  Obama seems shockingly fine with watching ISIL perpetrate a holocaust against Christians so long as those Christians are given the option to convert to Islam or agree to pay a completely arbitrary tax in order to avoid being executed.  The Yazidis aren't being given those options--ISIL just wants them all dead.  That shouldn't make the Christians being persecuted any less sympathetic though, should it?  Agreeing to live with someone's boot on your neck for the rest of your life doesn't seem like a much better option than death.  Maybe you need to be a law professor to see that distinction.

I have to ask, is Obama a Christian?  I know he calls himself one, but is he really?  I'm not asking to be a dick, or a Puritan, or whatever.  I'm actually agnostic, myself.  But I have to ask how a Christian could sit there and watch what's been happening to his fellow Christians in the Middle East lately and not want to do something about it.  How does a Christian watch an 1,800-year-old church being burned to the ground and do nothing?  The same group doing all these horrific things has been pretty open about wanting to hurt the United States however they can, yet Obama kept looking the other way.  I'm glad to see that Obama was finally dragged kicking and screaming into the White House Situation Room, but why would it take the plight of the Yazidis to do it?  (Yes, the strikes were meant to protect the consulate in Erbil, but Obama specifically mentions the Yazidi situation as an additional reason for them while neglecting to mention any of the horrors being inflicted upon Christians.  Why?  And will the Yazidi ultimately be left twisting in the wind anyway once Obama decides that Erbil is secure?)