Column wide file binding

What is the best way to bind files in column wide?
Looks a simple, but I don't know the most economic way.
I tried to merge, and cat function, but not success!!

Ex.)
file 1
1 2 3
2 3 4

file 2
3 4 5
4 5 6

file 3
2 3 4
1 2 7

I would like to see the result below
file 4
1 2 3 3 4 5 2 3 4
2 3 4 4 5 6 1 2 7

Thanks,

paste -d' ' file1 file2 file3

sweet!!
Thanks Shell_life.