Imagine the tables were turned and it was revealed our intelligence agencies had interfered with a foreign country's elections.  No need to imagine, it has happened repeatedly in the past and no doubt will continue into the future. 
One might also question why this nation's cyber defenses in general are so weak? Complacency? We just assume that nobody else will mess with us because we think we're the big dog? Arrogance and complacency, a bad combination.