Count your tricks, not your points. You can reasonably expect to make a one (spade) contract under the circumstances.

First, you have a solid six card suit headed by QJT, which guarantees one “top” trick. You can also expect to make three “long” tricks with the suit as trump. The two side kings are worth half a trick apiece; count them as one trick bringing the total to five.

With everyone passing, partner will have between 8 to 11 points (someone would probably have opened with 12). That represents about three tricks, within a range of two to four. You’re quite safe at the one level, and if an opponent sticks in an overcall, you can compete at least to two. Moreover, your suit is spades, so the opponent’s can’t outbid you at the one level, and probably not at the two level.

It’s true that a non-descript ten points might be worth only three tricks with a flat 4-3-3-3 distribution, and partner’s presumed three would bring the total only to six. In this case, you have five tricks in hand, not three, and are in a position to bid (and make) a low level contract.

Relative to its point count, your hand’s only weakness is that it has no aces, but otherwise it is highly upgradeable. Give your partner the two minor suit aces (eight points), and your two hands are worth eight and a half tricks (versus five in your own hand). A contribution of QJ of diamonds and Q of clubs (five high card points) by partner also improves you hand by nearly four tricks, leaving a fifth trick for a king or ace. Give partner 11 points in the form of A of hearts, king of spades or hearts and two minor suit queens, and game is not out of the question.

Take away the jack of spades, and I would not open. It’s “only” one point, but a critical “connector” in a critical suit. On the other hand, take away the Jack of clubs or downgrade one of the minor suit kings to a queen (also leaving nine points), and I would open one spade unless this was an event where this was not “legal.”