There's no such thing as strategic surprise - but there can always be tactical surprise
This is generally taken to be a memo item for commanders (particularly those many who are somewhat lacking in native creativity) to incorporate in their plans a carefully thought-through surprise for the enemy. Just because it's clear to all that you are poised and ready to attack, doesn't mean you should simply blow the starting whistle and advance in a line on the obvious axis (think Normandy 1944). It's all closely bound up with deception, another strongly advisable tool for every commander to pack in his kit - and much emphasised in British military doctrine, often to the bewilderment of more linearly-thinking allied leaders.
But it's also good advice for commanders who are themselves the ones mostly obviously holding the initiative on the battlefield. Maybe the other side isn't going to take your next powerful move lying down: perhaps something really unexpected is going to come flying over the battlements in your direction. No plan benefits from being thrown even a little off-balance before you've got properly started.
By the January of thirty years ago, it was pretty obvious to Saddam that he was about to face a formidable aerial bombardment. Far from concealing it, Bush's coalition had been keen he should understand the sheer might of the aviation they possessed - not least to deter a further invasion, into Saudi Arabia, before coalition ground forces were ready. Enough, you'd think (or indeed hope), to cow even a tooled-up maniac like Saddam, who'd had his share of setbacks against a much lesser foe in Iran.
But, just as we'd been surprised by some of the military innovations the Iraqis had come up with over the course of that earlier conflict, we had to cater for several initiatives we hadn't necessarily, errr, expected in detail...
1. The Scud campaign
We knew he had Scuds, including some with chemical warheads. We'd deployed very advanced kit to detect their launches, and accurately predict their trajectories (all of which worked very well, incidentally). We were searching diligently for the launchers as best we could, across the whole of Iraq.
What we hadn't banked on was an immediate Scud assault on Israel, as soon as we opened hostilities at the end of Desert Shield / start of Desert Storm, on 17th January 1991.
I mean: Saddam had seen the world's response to his attack on modest little Kuwait. Who, in his shoes would choose to open a new front against Israel ? But he did. I'll be writing more about Scuds in future installments.
2. Iraqi airforce decamps to ... Iran!
Yup, as Desert Storm commenced a large number of Iraqi planes headed immediately eastwards over the Iranian border, and landed there. To be fair, this is nowadays mostly attributed to individual (albeit clearly pre-planned) defections rather than a cunning ploy to preserve the Iraqi airforce. Still, it didn't half give us pause for thought. In conjunction with the attack on Israel ... does he have an *understanding* with Iran ..?
3. The attack on Khafji (Saudi Arabia)
Now this really is a classic. The defender makes the first move, catching the attacker unawares. As Wiki has it:
Saddam Hussein, who had already tried and failed to draw Coalition troops into costly ground engagements by shelling Saudi Arabian positions and oil storage tanks and firing Scud surface-to-surface missiles at Israel, ordered the invasion of Saudi Arabia from southern Kuwait.
Yes, that was the point: still, in January, we weren't ready for ground fighting. The aerial phase was always going to come first, but ideally we might have moved to ground ops rather sooner: as mentioned before, the logistical challenges were great, but the weather would soon be heavily against us. The shelling was no great surprise, but Khafji was. I leave you to refresh your memory on that episode on Wiki.
Gotta have realistic respect for the other side. He was making a proper fight of it - and not everyone thought he would. Surprise, eh? Catches you every time.
** not just military in its application, of course. Just because I know I'm going to die, doesn't necessarily mean I won't be caught out when it actually happens