Republican senatorial candidate Bob Keenan said Thursday there should be an end to the “birth tax’’ and accused Sen. Conrad Burns, R-Mont., of increasing taxes on college students and their parents. Keenan, on a road-trip campaign around Montana in an RV, said all the talk about ending the death tax is really meaningless when compared to the “birth tax,’’ the name he has given to the national debt that now stands at more than $8 trillion dollars. Keenan said every child born now inherits its individual birth tax of $30,000 — his or her portion of the national debt.