The political highlight of this week was supposed to be Donald Trump flying to China to meet with Xi Jinping. Now there are doubts whether this will even happen, or whether it will be postponed yet again. This summit meeting was initially scheduled for the middle of last month, but it had to be postponed because of the war Trump had started with Iran. Trump had hopes of wrapping the whole war up in early April just before he went to China, but those hopes were (obviously) never realized. This time around, Trump could actually decide to start attacking Iran once again, unilaterally ending the fragile ceasefire and escalating his war of choice. If this happens, it is doubtful whether Trump would spend a few days in China during a critical phase of the conflict, but then again with Trump, you never know what he'll wind up doing.

Today the prospect of reaching a short-term deal with Iran seems to have fallen apart completely. Last week, the U.S. proposed a one-page deal (Trump famously refuses to read long documents) that would have had a solution to the short-term problems both countries faced, while pushing out until later negotiations on the longer-term issues. The Strait of Hormuz would have been opened, the U.S. blockade of Iranian ports would have ended, and the war would have been declared over. Then a 30-day period would have begun, where issues such as Iran's nuclear enrichment and U.S. sanctions would have been discussed, with a long-term deal to (hopefully) follow. That was the plan, at any rate.

Both sides may yet come to some sort of similar arrangement, but the effort to strike such a deal has for now collapsed. Trump reportedly had added in a demand that Iran completely give up all nuclear materials (the 970 pounds of highly-enriched gaseous uranium that Trump idiotically keeps calling "nuclear dust"), forever forswear all ambitions for a nuclear bomb and forever end all uranium enrichment. The Iranians ignored Trump's urging to quickly respond and took their time. They eventually rejected Trump's proposal and floated one of their own -- which would have lifted all U.S. sanctions and provided for war reparations to be paid to Iran (with the uranium issue to be decided later).

Each side overreached, obviously. Each side wanted to claim a clear victory without any hint of compromise on the enemy's demands. But that wasn't supposed to be what this short-term limited deal would contain (at least, not from the public announcements of it last week). So eventually both sides could still back down on their maximalist add-ons and return to the original concept: removing the cause of economic pain while negotiations over the bigger issues are given time to play out. For the U.S., this would mean oil tankers once again safely transiting the Strait, and for Iran it would mean all shipping would once again resume to and from their ports.

But now we've got the China trip in the middle of it all. This may mean a one-week pause in any serious negotiations with Iran, since Trump will be distracted by trying to cut favorable deals with China.

A lot of time has gone by since Trump's last visit to China, in 2017. During it all, Xi has gotten much stronger. And now Trump is in an especially weakened state. He may have to beg for China's help in ending the war, since China is Iran's biggest customer for its oil (which gives China leverage, obviously). Trump has also had his favorite international political toys taken away from him by the Supreme Court -- he can no longer throw a tantrum and announce 145 percent tariffs willy-nilly anymore. And China has proven that it has its own leverage over the U.S. economy -- leverage that is much more powerful than the Strait of Hormuz, in fact. China's absolute worldwide monopoly on processed rare-earth minerals gives it a chokehold on not just consumer electronics (America would be hard-pressed to build things like automobiles without a steady supply of rare-earth materials) but also pretty much all the high-tech weaponry America builds as well. This chokehold hasn't gotten anywhere near as much attention as the closure of the Strait of Hormuz, but it would have far more drastic consequences if China decided to just completely shut off the supply to America.

China's Xi knows full well that any agreement or deal with Trump isn't really worth the paper it is written on (if it's even written down). The Chinese know he'll tear it up at the drop of a hat, if he goes into a tizzy for whatever reason. They also know the dynamics of the American political system, and are quite likely to delay any big deals until after the midterms -- when Trump could be even further weakened. And they know that the longer oil prices remain sky-high, the domestic political pressure on Trump will only increase -- which all means the more time goes by, the weaker Trump (and America) will get.

And above all else, China's Xi knows that America is now in absolutely no shape to do any saber-rattling whatsoever over the fate of Taiwan. Xi is no fool. He has sat back and watched the degradation of America's arsenal of high-tech weaponry over the past decade or so. First, there was the Ukraine war. America has been supplying some interceptor missiles to Ukraine, although the supply has been intermittent and has not included the best weapons America has. Then Trump waged a little mini-war with the Houthis in Yemen, because they were also trying to control the world's shipping lanes with threats of missile attacks. During this conflict -- which most Americans barely even paid attention to -- we used up our own missiles (both offensive and defensive) at an alarming rate, while fighting rebels in a very small country. Then Trump and Israel bombed Iran's nuclear facilities for 12 days last summer -- which also used up a large number of our high-tech weapons.

All of this meant America entered into the new war with Iran with already-depleted stockpiles of these weapons. And then we used them up at an incredibly quick pace during the opening phase of the war, further shrinking our reserves. These weapons cannot be rolled off the assembly lines line Ford Broncos -- they cost so much and are so complex that a very limited number of them are produced each year. Trump has been trying to get the production lines beefed up, but that sort of thing doesn't happen overnight. If we doubled or even quadrupled our current production rates, we would still be using them up far faster than we can replace them.

All of that assumes that we even can continue to build them, because they all require rare-earth materials for their construction.

Added into all of this is the fact that last week it was announced that we had agreed to sell $17 billion worth of interceptor missiles to the Gulf states (this is in addition to multibillion-dollar agreements we had already made to sell them ever more), since they have also run through their stockpiles of such weapons defending against Iranian attacks. So America doesn't just have to worry about replenishing our own reserves of these weapons, we've also got to re-arm our allies in the region. And remember, we can't even make enough to replace our own stocks of them any time soon.

Xi knows all of this. And he knows full well that a modern war will depend not so much on what happens on Day One, but what the military situation is like on Day 30 or so -- when the stockpiles of high-tech weapons aren't just dwindling but may have completely been used up. Modern wars -- even going back to World War II -- are wars of attrition of military equipment and the relative strength of production facilities to replace that equipment. We won World War II in large part because our factories and shipyards could churn out so many ships, tanks, and planes that neither Germany nor Japan could keep up.

Today, China has an enormous advantage in production capabilities. They can crank out cheap drones by the thousands (or even by the tens of thousands) while we were struggling to build our missiles by the hundreds (at best). Are we really going to use all of our stockpiles up to defend Taiwan? For how long?

That is the geopolitical equation Xi must be pondering right about now.

Trump was in a weakened state even before he launched his war of choice with Iran. Now he not only is even weaker, but he has new priorities to try to get China to agree to -- which lessens the chances that other priorities will be addressed. It wasn't looking like this summit was going to produce anything Trump could come home and brag about before, and now it looks even less likely to produce much of anything.

And that's if the summit even happens this week. If Trump does decide to start bombing Iran again, this summit may have to be postponed once again. In that case, Trump will be in an even weaker position when it does finally happen.

-- Chris Weigant

Follow Chris on Twitter: @ChrisWeigant