Political ...

By contrast there seems to be no reason why limericks can't be used for making political points. They are probably best used for poking fun at ineptitude. They will of course enjoy a short life.

For instance, the recent flooding in the North has done little to enhance the reputation of the Environment agency for water management. One bright spark apparently claimed that the flood defences were working quite well.  Presumbly the water had no right to go over the top. So:

All hail to to the wondrous EA
The masters of bodge it and pray
All of that water
Shouldn't have oughter
Won't somebody take it away?

After the obligatory quasi-royal visit I can imagine Cameron convening a meeting of his advisors at which one brain comes up with an idea.

Said Cameron "now listen up you lot
I just love the idea that he's got
What we shall do
Is set up a review
And spin it out longer than Chilcott"

And:

What we need is clearly a rethink
Northerners won't tolerate much more stink
But Osborne won't pay
So all I can say
Is push off to Annie's for a stiff drink