Why has the steel guitar been so popular in country music?

I believe it's because the tone of the steel guitar sounds like weeping...which makes it pair very well for "cry in my beer" songs. The relative absence of steel is one reason why today's country doesn't "sound" country.

Robert Randolph uses it a lot, but he's not country.

I believe I've also heard pedal steel in quite a few rock songs as well, including a song or two by Cinderella's.

Then, I believe there might be a lot of pedal steel in Hawaiian music as well.

However, it does seem to be most often used in country. I guess it's just the sounds it creates. Of course, a lot of guitarists--including Brad Paisley--use stringbenders on the G or B string of their guitars which basically creates a pedal steel-like bend and turns a guitar lick into a pedal steel-sounding lick.

Because of people,like Tom Morrell many mainstream country music listeners have heard him in session work"the sound in Your mind"Asleep at the Wheel[Tribute to Bob Wills and the Texas Playboys]Willie Nelson and many others.His contemporaries in western swing consider him a musical genius.Tom Morrell was inducted into the steel guitar hall of fame in 2001.