For any frontline correspondent covering a war there are two working maxims.

The first, is "no access, no story". The second, is that "things are rarely as they appear". I was reminded of these professional tenets again this week as the crisis in Syria escalated over the Damascus regime's alleged use of chemical weapons against its civilian population in the Ghouta area.

Up until those pictures of innocent victims gasping for the breath of life appeared on our television news, Syria's civil war had all but fallen off most people's radar.

"It's a dreadful thing to admit but, within days of those pictures, the Disasters Emergency Committee Appeal (DEC), got a substantial lift in public donations," one humanitarian worker admitted to me the other day.

This again is welcome proof that, as long as people are aware of the horrors unfolding in war zones, they will continue to care about the plight of innocents cynically targeted by combatants.

The problem with Syria's conflict, of course, is the extent to which correspondents are finding it increasingly difficult to report on. The two most pressing challenges are the physical dangers and a complexity that makes distinguishing fact from fiction problematic. Quite frankly, media coverage of the war is currently providing no more than a glimpse of the horrors unfolding daily. Reporters trying to gain access face kidnapping threats from jihadist and criminal groups or an uncertain fate should they be caught accompanying rebel fighters by the Syrian regime.

I well recall my first efforts to cross the border clandestinely from Turkey into Syria and the unscrupulous war profiteers who were adamant they worked for the rebel cause but were only interested in financial gain.

Faced with these challenges, many news organisation are now shying away from deploying their reporters, relying instead on so called "citizen journalism" of the kind that brought out images of the recent chemical weapons attack. Citizen journalism has its place providing invaluable access and material in instances when professional news gatherers are absent. That said, too often in Syria it has also become citizen or activist propaganda. Not for a moment am I suggesting the images from Ghouta were fabricated. That now is beyond question. There is, however, overwhelming evidence of instances where images and stories are manipulated or constructed by both sides in an attempt to gain political advantage. As one colleague aptly pointed out, "Damascus prides itself on being the oldest, continually inhabited city in the world, but also has a lengthy history of rumours passing for fact."

Given this and the fact we now sit on the brink of military intervention, it is more important than ever that independent professional reporting prevails in our coverage of Syria's war. My Sunday Times colleague and friend Marie Colvin and other journalists died in Syria adhering to such principles. It has often been said that in war truth is the first casualty. As professional news gatherers, we need to report what we don't know, as well as what we do about Syria. Above all else we need to be there. Too much is now at stake simply to accept our politicians' version of events.