Politics can be a noble trade.
Think of those who have campaigned for better mental health. Or Lord Dubs’s commendable efforts to offer sanctuary to child refugees.
Then there was today’s Prime Minister’s questions.
This was politics at its most vicious, grubby and depressing.
It was never going to be an easy outing for Jeremy Corbyn.
For the last week he has been struggling under the weight of accusations that he has failed to act on anti-Semitism .
Nor has he been able to escape some of words and actions when a backbencher.
Today David Cameron got into the bear pit and indulged in an act of blood sports which should not be tolerated in a compassionate country.
This all about point scoring ahead of tomorrow’s elections and in every response the Prime Minister went for the kill.
Inevitably, he was going to attack Corbyn over anti-Semitism.
For once, the Labour leader came prepared and used his opening remarks to note it was Holocaust Memorial Day in Israel and he utterly condemned any form of anti-Semitism.
A more gracious Prime Minister, one who did not want to sow further division, might have welcomed Corbyn’s humility.
Cameron just bared his teeth and tore into Corbyn for once describing Hamas and Hezbollah as “friends.”
The Labour leader’s explanation - that he did not approve of these organisations - was never going to be satisfactory.
The Prime Minister then repeated his attack on Sadiq Khan for sharing a platform with Suliman Gani, an alleged “extremist” with reportedly unpalatable views on gay marriage and women’s rights.
With patience but not enough bite, Corbyn noted that Gani was a Conservative supporter and called on Cameron to denounce the divisive campaign of Zac Goldsmith.
With an eye only on the ballot box, Cameron shot back that Corbyn was a “friend of Hamas but an enemy of aspiration.”
Between these wretched exchanges the Labour leader asked a series of questions about the cuts to social care, the housing crisis and child poverty.
None of this will be remembered once the blood has been swept from the Commons’ floor.