Turkey is arguably the strongest power in gunboat. I'd personally say 2nd to France.
The ability of the other powers to dig out Turkey is so small, you can stick around in the game at 4 or 3 centers for years and years and nobody can successfully attack you. And if your neighbors give in to infighting, you can likely attack 2 or even all of them simultaneously and still do well.
In a press game, your neighbors can make deals and coordinate their moves to dig you out - but it's extremely difficult in gunboat. For example, if Russia controls Rumania, Austria controls Serbia, and Italy controls Greece, you might be able to keep Bulgaria without even doing any support-holds, even if all 3 players are hostile to you. You'll almost certainly get into Black Sea in 1901 and are rarely ever forced to leave it. With this kind of defense, it's probably impossible for your neighbors to take you out unless another of your neighbors has first been wiped out (e.g., Austria often has to crush Russia and/or Italy in order to invade Turkey).
Even if there is a strong alliance somewhere on the board, you'll probably be the last player eliminated, so if one of them goes for a solo win you have a chance to make it into the draw.
With good guesses and clever tactics, you can turtle a very long time until some situation appears where you can make a powerful guess and EXPLODE, expanding very quickly. If the 3 western powers are still at war when this happens, you have a good chance of a solo win.
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