CLIMATE CHANGE

Joe Biden (D)

Talks a lot about reducing energy consumption but has yet to come up with a master plan beyond supporting a system to reduce carbon emissions 80 per cent below 1990 levels by 2050.

Hillary Clinton (D)

It took her until last November to come up with a serious cap-and-trade system that would cut greenhouse-gas emissions by 50 per cent from 1990 levels by 2050. Her focus is efficiency and investment.

John Edwards (D)

A prime mover on climate change, which he sees as an engine to revitalise the economy by creating "green jobs" for skilled Americans whose jobs have gone to China and India.

Barack Obama (D)

Began his campaign with platitudes and horrified the green lobby by initially backing ideas for liquefied coal. Then provided a detailed plan that would reduce emissions by 80 per cent and auction all pollution permits.

Rudy Giuliani (R)

Believes in energy independence, by which he means "not sending money to terrorists" in Saudi Arabia. Loves nuclear power, coal, drilling for oil and gas, opposes mandatory emissions cap.

Mike Huckabee (R)

Delights crowds with his feverish talk of energy independence for America in 10 years. Promises to tell Saudi Arabia to keep its oil: "We don't need it any more than we need their sand."

John McCain (R)

A maverick Republican who "gets it" about global warming and doesn't mind telling Iowa farmers that he would cut off their $3-a-gallon subsidies for ethanol. Equally against hand-outs to Big Oil.

Mitt Romney (R)

Carefully dodges the issue of whether he even believes in global warming. Only interested in voluntary action. He is keen on drilling for oil in places like Alaska's pristine wilderness, nuclear, and biofuels.

WAR IN IRAQ

Joe Biden (D)

Voted for war and now wants the troops home by the summer. Wants a unified Iraq "by decentralising it and giving Kurds, Shia and Sunnis their own regions. Calls the war "a mistake".

Hillary Clinton (D)

Famously refuses to apologise for voting for a war, which she now opposes. Would leave troops in Iraq to fight al-Qai'da and train the Iraqi Army. Would begin a phased withdrawal within 60 days of taking office

John Edwards (D)

With skills honed in the courtroom, he now explains away his vote for war by saying it was a mistake. Advocates a more rapid and complete troop withdrawal from Iraq than his rivals.

Barack Obama (D)

"I am not opposed to all wars, I am opposed to dumb wars," he said before the latest Bush adventure. Would keep a limited force in Iraq after withdrawing combat units at the rate of one or two per month.

Rudy Giuliani (R)

Says the Iraq war led Iran to abandon its nuclear weapons programme: "We're at war. They want to come here and kill us so we've got to put Iraq in the context of a much broader picture than just Iraq."

Mike Huckabee (R)

Won't let his background as a preacher get in the way of a good war. Opposes withdrawing the troops and says that "despite what the gloomy Democrats in the US profess, reconciliation is happening in Iraq".

John McCain (R)

Backed the troop increases and opposes withdrawing forces. His support led to a near collapse of his campaign, but as the surge has reduced violence in Iraq, his campaign has bloomed again.

Mitt Romney (R)

Believes in the war on terror. "Violent, radical jihadists want to replace all the governments of the moderate Islamic states. And to do that, they also want to bring down the West, in particular us.'

FOREIGN POLICY

Joe Biden (D)

Turn on the TV whenever there is a crisis and up pops windbag Biden laying into the president on Guantanamo, Iran and Pakistan. He opposes military action as a way of dealing with Iran.

Hillary Clinton (D)

More hawkish than many Republicans, especially on the Middle East and Israel. Says America's military should not be limited to "splendid little wars". She would bomb Iran if she thought it would help.

John Edwards (D)

The only candidate willing to push unconventional ideas such as linking US aid to human rights and democracy a practice that would quickly disqualify key allies, such as Egypt and Pakistan.

Barack Obama (D)

Has impressed European diplomats by his willingness to embrace multilateralism. Blamed for not having a lot of experience. He would meet leaders of Iran, North Korea and Syria without preconditions.

Rudy Giuliani (R)

"Worse than Bush and scarier" is the common assessment of his foreign policy plans. Rudy wants to press ahead with cruel and inhuman treatment as an instrument of foreign policy.

Mike Huckabee (R)

Has so little foreign policy experience it's frightening. "Rather than wait for the next strike, I prefer to cut to the chase by going after al-Qai'da's safe havens in Pakistan." That's right, invade Pakistan.

John McCain (R)

When asked if America would "send an air-mail message to Iran". He began his answer by singing "Bomb bomb bomb, bomb bomb Iran", to the tune of The Beach Boys' song "Barbara Ann".

Mitt Romney (R)

A Bush sycophant on foreign policy, says "the military option remains on the table" with regard to Iran. Thinks Americans should be "saying thank you to the president for keeping us safe these last six years."

HEALTHCARE

Joe Biden (D)

Wants to bring in universal healthcare and pay for it by ending the war in Iraq and rolling back President George Bush's tax cuts for the richest.

Hillary Clinton (D)

Her greatest failure during her White House years is now her biggest challenge. The Clinton plan would require every American to get health insurance. It would be paid for by rolling back Bush's tax cuts.

John Edwards (D)

Wants health coverage for the 47 million Americans who don't have any. "We're going to bring down costs for everybody. And for most Americans, we're going to help them pay the cost."

Barack Obama (D)

Promising to bring about quality affordable healthcare for all, has nonetheless balked at promising immediate universal care. Would require all children to have health insurance; pay for it by rolling back tax cuts for the rich.

Rudy Giuliani (R)

Only interested in consumer-based system and opposed to making it the law that everyone is covered. Says the last thing the government should be doing is running America's healthcare system.

Mike Huckabee (R)

Plan is for prevention rather than cures. He opposes universal healthcare. "We do need to get serious about preventive healthcare instead of chasing more and more dollars to treat chronic disease."

John McCain (R)

Thinks universal healthcare can come without the government. "I'm certainly not interested in raising people's taxes." For free-market, consumer-based system; pledged affordable health.

Mitt Romney (R)

Stridently opposes "socialised medicine", saying: "The way we improve something is not by putting more government into it... Instead, the right way for us to go is to bring in place market dynamics."