A few thoughts.
1. The problem of labels is it invariably leads you to wrong solutions. I see a lot of progressives casually tossing around phrases like "colonialism" and "genocide." Leaving aside the morality issues, the problem of regarding the Israel/Palestinian conflict as a "colonial" conflict is there is no home country for the "invading" Zionists to return to. Anti-colonial resistance worked on a theory that you could exhaust the mother country and push the colonialists to return from whence they came. The sole exception to this was South Africa, where peace was established with the white minority by transferring political power to the majority while retaining economic power in the hands of the white minority.
Insisting that the Palestinian struggle is an anti-colonial problem rather raises the question of where you expect 7 million Jews to go. The usual answer to this is that they shouldn't have been there in the first place. OK, but they are there, and whether Germany "should" have been forced to cede land for a Jewish homeland is irrelevant. For U.S. progressives, I will note that your argument is essentially the same as that of conservatives for why we should keep trying to deport 12 million "illegals" despite the fact that any rational person will tell you that this is simply not a realistic possibility.
I recognize that the virtue of characterizing the Israel/Palestinian struggle is that it justifies violence by Palestinians to Israelis that inflict indiscriminate civilian casualties (or at least try to) while still allowing you to condemn Israeli violence against Palestinians. Anti-colonial struggles are justified because the presence of the invader is unjustified and the colonial power is to be driven off by any means necessary. The act of the colonizer living in the colony is itself the act of aggression, which justifies the violent response. When the colonial power withdraws, peace is achieved.
But as noted here, 7 million Jews are not going anywhere. It is a much better frame to view this as a standard war between sovereign states when one sovereign state is pissing on the other sovereign state. The resolution of that conflict is a negotiated settlement which does not involve mass relocation of the losing nation's population.
Similarly, the use of the word "genocide," as opposed to say "unwarranted aggression" or even "terrorist act," leads to an unfortunate misjudgment. In war, or even terrorism, the killing is a means to an end. In genocide, the killing is an end in itself. Even where the enemy is indifferent to civilian casualties, or even targets civilians as a means of intimidating the population of the enemy, the death toll is not nearly as dramatic as when killing is itself the object. Perhaps more importantly, war (whether fought conventionally or through "terrorist" tactics) is a rational enterprise designed to achieve a specific objective other than the death of the opponent. It can therefore be negotiated to a cease fire more easily than an actual genocide.
The capacity for true genocidal rage exists in the Israeli/Palestinian conflict. If that happens, we will see casualty counts on both sides that will make the current hostilities seem like a happy day in the park. Those who conceive of the current conflict as genocide lack imagination, and therefore pursue strategies that are based on an assumption that this is as bad as it gets.
2. From the perspective of Hamas, this was the ideal time to provoke an outright confrontation. they also needed to do something to preserve their political position. The problem for Hamas (and Abbas) is that life for Palestinians in Gaza is improved, but stagnant. When people feel their lives are at stake, they rally around their leaders. When people feel their lives are going nowhere, they start to think about change. For over a year, the sentiment among Palestinians has been to see reconciliation with the Abbas led PA (especially when it looked like the West Bank was on track for statehood). Hamas, for its part, is dealing with the problem of trying to be a government when you are blockaded and under sanctions.
So time to circle back to see if the military strategy can alter the status quo. For Hamas, the situation has improved considerably since 2009. The change of government in Egypt, combined with the interest of Syria and Iran in supporting armed resistance (both could use an Israeli/Palestinian war as a rallying point), give Hamas both greater access to firepower and the hope of supporting missile fire from Lebanon, Syria and "militants" in the Sinai.
3. It feels to me like Israel ramped up ground assault much more quickly than anticipated because the Hamas armament is significantly more powerful and plentiful than anticipated. Iron Dome has limits. The supply of anti-missiles run out eventually. Further, the longer this drags on, the more information Hamas gains on Iron Dome's technical capabilities. If we assume that Lebanon, Syria and Sinai could also participate in coordinated missile attacks, it is entirely possible for them to overwhelm Iron Dome. Historically, Israel's strategy to avoid multi-front wars is to strike quickly on one front to eliminate the opponents operating capability so it can then reorient its forces to a new front. This worked in '67. Israel failed to do this in '06.
So from Israel's perspective, with no prospect of stopping Hamas rocket fire through airstrikes any time soon, and no sense of Hamas' actual armament, and facing the real possibility of exhausting its Iron Dome capabilities, Israel opted to strike quickly.
4. I am not actually sure what Hamas' end game is. It is possible they believe that the rest of the Arab world will finally join them in crushing the Zionist entity. I think more likely they hope to inflict sufficient damage on Israel to achieve a negotiated settlement.
All in all, the potential for this to spin out of control and lead to massive, long-term war is pretty high. hence my analogy to 1913. Te conflicting alliances and popular sentiments at play make brutality by both sides on a grand scale entirely plausible -- the more so because both sides continue to make fundamental miscalculations about the level of force the other will use to retaliate for what it views as provocation.
Happy Rosh Chodesh.