Israel is well aware of the extent of both Syrian and Iranian involvement in the ongoing Hizbullah rocket offensive - as the sources of weaponry, and much more besides. The Teheran-Damascus axis, as Prime Minister Ehud Olmert stressed in his Knesset speech on Monday night, is subcontracting terrorism - to Hamas and to Hizbullah.
The rockets now daily hitting Haifa and points ever-further south are Syrian made. The missile that hit the Hanit vessel off the Lebanese coast on Friday was Iranian-made. Iran is reported to have several hundred of its own Revolutionary Guards based in Lebanon, working with Hizbullah; some of them may well have been killed in the Israel Air Force's raids on Hizbullah's Dahiya command neighborhood in the southern suburbs of Beirut.
But Israel remains determined, so far as it is able, not to have this conflict escalate to include those two enemy states. Indeed there is a concern in the defense establishment that Hizbullah, isolated and struggling for survival amid the intensifying IAF strikes, may resort to desperate measures to try and draw in the Syrians - including even firing itself on a Syrian target, an attack that would be misrepresented as Israeli fire in the hope of prompting the already jumpy Syrians into injudicious action.
From the Israeli point of view, Lebanon is the sovereign power from whose territory Hizbullah has been allowed to operate and in whose territory it has established its military infrastructure. That's where the quarrel is, and that's where it is playing out.
In terms of the parameters of this conflict, Israel has its register of targets, and intends to strike at them until, it hopes, it reaches the stage where Hizbullah can no longer be counted a significant threat to Israeli territory. Even a unilateral Hizbullah cease-fire would not halt those air sorties.
Israel is also interested in minimizing its use of ground forces as it seeks to destroy Hizbullah's missile capability; it is relying on the IAF to do the lion's share of the work. It also has no intention of carving out a semi-permanent new security zone, occupied by the IDF, on the other side of the border where Hizbullah had made itself so comfortable; instead, again, it is relying overwhelmingly on the IAF to clear a strip a kilometer deep into Lebanon - a zone that it will continue to patrol by air and to which it will not allow entry.
The idea is to ensure that there be no repeat of the situation that prevailed until last week, whereby Hizbullah gunmen could eyeball Israeli soldiers meters away across the fence, and in which those same gunmen could lay an explosive charge so colossal just 70 meters across the border as to rip apart the Israeli tank that crossed the border in the immediate aftermath of last Wednesday's attack near Moshav Zar'it.
The rare degree of national unanimity behind this thinking was reflected in the respectful reception afforded Olmert in the Knesset on Monday night. For the first time in years, a prime minister was able to deliver a lengthy, nuanced address unhindered by heckling or other interruption. With Israel facing what he called "a moment of national truth," a man elected with an underwhelming majority spoke for a wider consensus than he ever has before.
Each passing day of the Israeli offensive against Hizbullah serves to emphasize the striking contrast between the attitude of this government and that of its immediate predecessors to Hizbullah's ever-bolder muscle flexing. The last time Sheikh Nasrallah tried his hand at a prisoner exchange deal, in 2004, Israel freed hundreds of prisoners for the captured "businessman" Elhanan Tennenbaum and the bodies of three soldiers. So it is easy to understand why he might have imagined a similarly glorious scenario, from his point of view, unfolding as he held up his two captured IDF soldiers as bargaining chips after last Wednesday's attack.
However improbably, with peacenik Amir Peretz at the Defense Ministry, a rather different Israeli response ensued: Not merely a readiness to take a calculated heavy risk on the lives of those two soldiers by hitting back at Hizbullah, but a readiness, too, to strike into residential areas of Lebanon where Hizbullah has secreted missiles. These were targets Nasrallah may have believed Israel would never have the stomach to strike, or the international tacit approval.
But the sheer inescapable gravity of the threat posed by Nasrallah, as underlined in the ongoing rocket attacks on Israel, has persuaded even some of Israel's less familiar friends of an imperative for military action. The daily reminders of the potency of Hizbullah's threat are also key to the near-unanimous Israeli public support for the offensive.
Nasrallah is now the victim of his accumulated strength. Had his rockets proved impotent, there would have been wider international resonance for those protesting the IDF's purported use of "disproportionate force," and wider local opposition as well. But with his Katyushas and their more dangerous variants exacting so heavy a daily price on Israel's citizenry, in a conflict that began with an unprovoked attack across a sovereign border, some of the usual international critics have been silenced, however briefly, and opposition within Israel has to date been marginal.
The IDF knows that even if it gets the week or so it believes it needs to largely dismantle Hizbullah, and the Lebanese army ultimately deploys in the south, the picture will still be far from cloudless. It is estimated that up to 50 percent of that Lebanese army is pro-Hizbullah in orientation - so, to some extent, Lebanon would be formalizing Hizbullah's presence on Israel's doorstep again. Were pro-Hizbullah forces in that army to open fire on Israel, however, the new policy in Israel would again be to hold the sovereign government in Beirut directly responsible. And direct responsibility can carry a heavy price.