The Philippines Are Finding Themselves Between a Chinese Rock and an American Hard Place

Last week, protestors in the Philippines got riled up about a recent ruling of the Philippine Supreme Court allowing the US military to use bases in the country, meaning that the US military will be back in the Philippines after a 23-year hiatus.

The ruling, which validates the constitutionally of the Enhanced Defense Cooperation Agreement the US and Philippines signed in 2014, is a bit more arcane about whose bases can be used by whom and under what conditions, but the long and short of it is that the Americans are back in the Philippines — right under the nose of the Chinese armed forces, within a short distance of areas of the South China Sea that China and the Philippines have been getting heated up over.

Islands are usually of great strategic importance. The Philippine archipelago consists of 7,107 of them — and happens to be very strategically important, indeed.

Which is a big reason the Philippines get invaded, conquered, colonized, and otherwise find themselves under the boot often enough to be the Poland of the Pacific. These guys just can't catch a break: They've been living underneath someone else's gun muzzles for most of the last half millennium, and fighting against those interlopers in some fashion or another for just as long.

Now, the Philippines are strategic because in strategy, as in real estate, location matters. Sure, they're on the edge of the South China Sea, and the South China Sea is super valuable, has a ton of oil, is crossed by all kinds of shipping lanes, and has some great fishing. But make no mistake: the importance of the Philippines goes far beyond that.

Related: China's Massive Tiny Land Grab Continues

Islands, or rather, collections of islands, can act as the maritime equivalent of a wall. The islands themselves channel ships into the gaps between them, and those constrained passages are great for naval mines. Meanwhile, the islands themselves are great for defensive fortifications and bases for missiles and patrol aircraft. And really, the only way to completely neutralize a heavily fortified island, short of nuking it, is to prepare for a bloody amphibious assault, followed by the savage and gruesome work of digging out a deeply entrenched opponent.

The Russians, like the Soviets before them, make use of the defensive characteristics of islands (in that case, the Kuril island chain between Russia and Japan) to safeguard the patrol zone for nuclear missile submarines in the Sea of Okhotsk, called a naval bastion. And if island chains are good enough to safeguard Russia's nuclear deterrent, don't write off the defensive potential of well-fortified island chains.

Let's say you're a hotshot Chinese strategist. Now, take a map of China and rotate it so China is on the bottom and the Pacific Ocean is at the top. The first thing a strategist from the country that built the Great Wall of China will see is a chain of islands standing between China and the vast expanse of the Pacific. In other words, the first thing a rising China sees in the Pacific is a wall.

That first and nearest chain of islands is called the "First Island Chain" by the Chinese, and acts as a wall running from north to south, starting with Japan and then going through a chain of islands that includes the US base at Okinawa. Taiwan anchors the middle of the wall, and then, finally, the southern sector is dominated by the Philippines.

Everything from warfare to commerce in and around the Pacific is dominated by sea and air power. If your own navy, be it Chinese or US, gets bottled up or otherwise shut out, you're going to find yourself fighting at a severe disadvantage

Now, looking again at Chinese expansion into the South China Sea, you can see there's a lot more than oil, fish, and trade routes at stake. The Chinese push into the area has the nice advantage of positioning significant force in a place to strike out and force a breach in the First Island Chain by going straight through or around the Philippines.

This is something the Chinese have a good chance of doing, just as long as the Philippines aren't heavily fortified. But if a sizeable hostile force gets good and dug in there, all bets are off for the Chinese. A deeply and heavily fortified Philippine archipelago would be nearly impossible to clear at anything less than horrific cost.

Fortunately for the Chinese, however, the last few centuries of invasion, occupation, and life as a distant colony haven't done great things for the Philippine economy or industrial base, so the Philippines are a far cry from being even remotely able to fortify every single island in the chain. And a chain is only as strong as its weakest link.

Related: America's Dark History in Philippines Casts Shadow Over Defense Pact

But all these assumptions go bust if the world's largest military is operating out of the Philippines, like the US did for most of the Cold War. A renewed US presence equivalent to the Cold War basing would mean that the islands would be a hell of a lot more than a speed bump to any Chinese plans to break out into the rest of the Pacific.

All this might explain why the US wants bases in the Philippines now, but it doesn't explain why the US had such a large Cold War military presence there. I mean, the US and China weren't really set up as direct, head-to-head military rivals back then.

That gets to a second way that islands can be strategically important: as transportation hubs. In this role, islands act like distant outposts, scattered about, breaking up the endless expanse of nothing at all. The Pacific Ocean is, above all else, gigantic. Unlike a Chinese planner looking east and seeing a wall, a US strategist looking west at Asia, from a country shaped by westward expansion, first sees thousands of miles of wide-open ocean punctuated by the occasional lonely island.

From this perspective, the first island outpost a US planner can rely on is Hawaii, which sits there in the middle of a vast ocean, looking a lot like a gas station in the desert with a big, lonely "Last Chance For Gas" sign swinging in the wind. Going further west from that outpost, there just aren't a lot of islands large enough, with good enough harbors, to be ideal for hosting a large military and logistical capability.

But, if you have an enormous military hub based in the Philippines, it becomes comparatively easy to project force throughout most of East and Southeast Asia. Without access to the Philippines, everything is just a much bigger pain in the ass. Not beyond solving, but a great deal more complicated.

And that's why the Philippines are such a critical and coveted spot on the map.

Related: US Marine Convicted of Brutally Murdering Transgender Woman in the Philippines

Now, Chinese pressure on the South China Sea has put the Philippines between a geostrategic rock and a political hard place that has to do with a lot more than just rights to the oil under the South China Sea. Heightened tensions in the South China Sea may or may not be the spark that lights off a larger conflict, but even if the sea weren't worth a damn dime, that wouldn't let the Philippines off the hook. Odds on, it would get sucked into any wider war between China and the US, like it or not.

But even if things do not escalate to that point, the geostrategic race between the United States and China means that Filipinos won't likely see the last of foreign military forces on their soil any time soon.

Follow Ryan Faith on Twitter: @Operation_Ryan